1990
53.
Y Maeno, S Awaji, H Matsumoto, T Fujita
Transport and magnetic properties of LaxSr1-xTiO3 Journal Article
In: Physica B: Condensed Matter, vol. 165-166, pp. 1185-1186, 1990.
@article{Maeno19901185,
title = {Transport and magnetic properties of LaxSr1-xTiO3},
author = {Y Maeno and S Awaji and H Matsumoto and T Fujita},
doi = {10.1016/S0921-4526(09)80178-6},
year = {1990},
date = {1990-01-01},
journal = {Physica B: Condensed Matter},
volume = {165-166},
pages = {1185-1186},
abstract = {We report the transport and magnetic properties of LaxSrl-xTiO3. Antiferromagnetic ordering of LaTi03 with the Neel temperature TN ≃ 110 K disappears in the presence of less than one percent of Sr. For a wide range of x, the resistivity exhibits a strong decrease for temperatures below about 40 K, which continues all the way down to 35 mK, although there is no magnetic anomaly. For x less than about 0.2, the transport properties are interpreted in terms of the presence of a narrow impurity band, which resides 20 - 200 meV below the bottom of the Ti 3d bands. © 1990, Elsevier Science Publishers B.V. (North-Holland). All rights reserved.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
We report the transport and magnetic properties of LaxSrl-xTiO3. Antiferromagnetic ordering of LaTi03 with the Neel temperature TN ≃ 110 K disappears in the presence of less than one percent of Sr. For a wide range of x, the resistivity exhibits a strong decrease for temperatures below about 40 K, which continues all the way down to 35 mK, although there is no magnetic anomaly. For x less than about 0.2, the transport properties are interpreted in terms of the presence of a narrow impurity band, which resides 20 - 200 meV below the bottom of the Ti 3d bands. © 1990, Elsevier Science Publishers B.V. (North-Holland). All rights reserved.
52.
Y Maeno, N Kakehi, A Odagawa, T Fujita
Structural transitions and superconductivity in (La1-xBax-ySry)2CuO4 Journal Article
In: Physica B: Condensed Matter, vol. 165-166, pp. 1689-1690, 1990.
@article{Maeno19901689,
title = {Structural transitions and superconductivity in (La1-xBax-ySry)2CuO4},
author = {Y Maeno and N Kakehi and A Odagawa and T Fujita},
doi = {10.1016/S0921-4526(09)80430-4},
year = {1990},
date = {1990-01-01},
journal = {Physica B: Condensed Matter},
volume = {165-166},
pages = {1689-1690},
abstract = {We report on the interplay among the structural transitions, transport anomalies and superconductivity in (La1-xBax-ySry)2CuO4. Here the amount of doping is held at x = 0.0625 and the structural transition temperatures are controlled by a parameter y. The appearance of the low-temperature tetragonal phase and the depression of superconductivity correlate well, but unlike in (La1-xBax)2CuO4 the transport anomalies can be decoupled from the structural transition, implying the presence of a new instability in the electronic state. © 1990, Elsevier Science Publishers B.V. (North-Holland). All rights reserved.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
We report on the interplay among the structural transitions, transport anomalies and superconductivity in (La1-xBax-ySry)2CuO4. Here the amount of doping is held at x = 0.0625 and the structural transition temperatures are controlled by a parameter y. The appearance of the low-temperature tetragonal phase and the depression of superconductivity correlate well, but unlike in (La1-xBax)2CuO4 the transport anomalies can be decoupled from the structural transition, implying the presence of a new instability in the electronic state. © 1990, Elsevier Science Publishers B.V. (North-Holland). All rights reserved.
51.
K Satoh, T Fujita, Y Maeno, Y Uwatoko, H Fujii
Specific Heat of a New Dense-Kondo System CeTIn (T = Ni, Pd, Pt) Journal Article
In: journal of the physical society of japan, vol. 59, no. 2, pp. 692-700, 1990.
@article{Satoh1990692,
title = {Specific Heat of a New Dense-Kondo System CeTIn (T = Ni, Pd, Pt)},
author = {K Satoh and T Fujita and Y Maeno and Y Uwatoko and H Fujii},
doi = {10.1143/JPSJ.59.692},
year = {1990},
date = {1990-01-01},
journal = {journal of the physical society of japan},
volume = {59},
number = {2},
pages = {692-700},
abstract = {Specific heat of a newly-found dense-Kondo system CeTIn (T=Ni, Pd, Pt) has been measured between 60 mK and 80 K. For CePdIn and CePtIn, the ratio of specific heat to temperature, C/ T, increases remarkably below 10 K, indicating the heavy-fermion nature. On the other hand, no enhancement of C/ T is observed for Ce-Niln, suggesting the valence fluctuating state. A sharp peak in C/ T is observed at 1.7 K for CePdIn, which is ascribed to an antiferromagnetic transition, whereas CePtIn does not show any signs of phase transition at least down to 60 mK. The variety of low-temperature behavior in CeTIn is discussed in terms of competition between the Kondo state and the RKKY interaction. © 1990, THE PHYSICAL SOCIETY OF JAPAN. All rights reserved.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Specific heat of a newly-found dense-Kondo system CeTIn (T=Ni, Pd, Pt) has been measured between 60 mK and 80 K. For CePdIn and CePtIn, the ratio of specific heat to temperature, C/ T, increases remarkably below 10 K, indicating the heavy-fermion nature. On the other hand, no enhancement of C/ T is observed for Ce-Niln, suggesting the valence fluctuating state. A sharp peak in C/ T is observed at 1.7 K for CePdIn, which is ascribed to an antiferromagnetic transition, whereas CePtIn does not show any signs of phase transition at least down to 60 mK. The variety of low-temperature behavior in CeTIn is discussed in terms of competition between the Kondo state and the RKKY interaction. © 1990, THE PHYSICAL SOCIETY OF JAPAN. All rights reserved.
50.
B Reihl, Y Maeno, I Mangelschots, K O Magnusson, C Rossel
Rigid band behavior of Nd2-xCexCuO4-y: A direct and inverse photoemission study Journal Article
In: Solid State Communications, vol. 74, no. 1, pp. 31-34, 1990.
@article{Reihl199031,
title = {Rigid band behavior of Nd2-xCexCuO4-y: A direct and inverse photoemission study},
author = {B Reihl and Y Maeno and I Mangelschots and K O Magnusson and C Rossel},
doi = {10.1016/0038-1098(90)90204-O},
year = {1990},
date = {1990-01-01},
journal = {Solid State Communications},
volume = {74},
number = {1},
pages = {31-34},
abstract = {We have employed ultraviolet photoemission spectroscopy at hν = 21.2 and 40.8 eV and inverse photoemission spectroscopy at hν = 9.5 eV to study Nd2-xCexCuO4-y (x = 0.0, 0.1, 0.15, 0.2). We observe a shift of the Fermi level to higher energies as a function of x. The total shift is 0.3 eV and saturates at x = 0.2. As suggested by existing band-structure calculations, this result seems to point to a rigid-band filling of the Ce-derived electrons in these "electron-doped" superconducting cuprates. © 1990.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
We have employed ultraviolet photoemission spectroscopy at hν = 21.2 and 40.8 eV and inverse photoemission spectroscopy at hν = 9.5 eV to study Nd2-xCexCuO4-y (x = 0.0, 0.1, 0.15, 0.2). We observe a shift of the Fermi level to higher energies as a function of x. The total shift is 0.3 eV and saturates at x = 0.2. As suggested by existing band-structure calculations, this result seems to point to a rigid-band filling of the Ce-derived electrons in these "electron-doped" superconducting cuprates. © 1990.
49.
K -i Kumagai, M Abe, S Tanaka, Y Maeno, T Fujita, K Kadowaki
Cu-NMR study on electronic state in electron doped Ln2−xCexCuO4 (Ln=Nd, Pr, Sm and Eu) Journal Article
In: Physica B: Condensed Matter, vol. 165-166, pp. 1297-1298, 1990.
@article{Kumagai19901297,
title = {Cu-NMR study on electronic state in electron doped Ln2−xCexCuO4 (Ln=Nd, Pr, Sm and Eu)},
author = {K -i Kumagai and M Abe and S Tanaka and Y Maeno and T Fujita and K Kadowaki},
doi = {10.1016/S0921-4526(09)80234-2},
year = {1990},
date = {1990-01-01},
journal = {Physica B: Condensed Matter},
volume = {165-166},
pages = {1297-1298},
abstract = {Antiferromagntic order of Cu moments is confirmed by the observation of zero field Cu-NMR for x<0.14 of Ln2−xCexCuO4 with Ln=Nd, Pr, Sm and Eu. The electric field gradient (EFG) at the Cu site is large in antiferromagnetic state, but is anomalously absent in the superocnducting or metallic region. We investigate the temperature- and x-dependences of the Knight shift and nuclear relaxation rates, and the effect of oxygen reduction on NMR properties. The results indicate that the electronic state in the system changes dramatically with Ce-doping, and is quite different from those of hole doped oxides. © 1990, Elsevier Science Publishers B.V. (North-Holland). All rights reserved.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Antiferromagntic order of Cu moments is confirmed by the observation of zero field Cu-NMR for x<0.14 of Ln2−xCexCuO4 with Ln=Nd, Pr, Sm and Eu. The electric field gradient (EFG) at the Cu site is large in antiferromagnetic state, but is anomalously absent in the superocnducting or metallic region. We investigate the temperature- and x-dependences of the Knight shift and nuclear relaxation rates, and the effect of oxygen reduction on NMR properties. The results indicate that the electronic state in the system changes dramatically with Ce-doping, and is quite different from those of hole doped oxides. © 1990, Elsevier Science Publishers B.V. (North-Holland). All rights reserved.
48.
B P̈mpin, H Keller, W K̈ndig, W Odermatt, I M Savić, J W Schneider, H Simmler, P Zimmermann, E Kaldis, S Rusiecki, Y Maeno, C Rossel
Muon-spin-rotation measurements of the London penetration depths in YBa2Cu3O6.97 Journal Article
In: Physical Review B, vol. 42, no. 13, pp. 8019-8029, 1990.
@article{P̈mpin19908019,
title = {Muon-spin-rotation measurements of the London penetration depths in YBa2Cu3O6.97},
author = {B P̈mpin and H Keller and W K̈ndig and W Odermatt and I M Savić and J W Schneider and H Simmler and P Zimmermann and E Kaldis and S Rusiecki and Y Maeno and C Rossel},
doi = {10.1103/PhysRevB.42.8019},
year = {1990},
date = {1990-01-01},
journal = {Physical Review B},
volume = {42},
number = {13},
pages = {8019-8029},
abstract = {Muon-spin-rotation (SR) experiments on a high-quality sintered YBa2Cu3Ox sample [x=6.970(1)] were performed, in order to obtain an accurate knowledge of the magnitude and the temperature dependence of the magnetic penetration depth in this copper oxide superconductor. Special attention was given to the data analysis. In particular, the systematic errors introduced by different types of analyses were estimated. Our results show that the temperature dependence of the effective penetration depth eff into the sintered sample is well described by the two-fluid model, with eff(0)=155(10) nm. This behavior of eff(T) is consistent with conventional s-wave pairing. With the anisotropy ratio cab=5(1) measured in a previous SR experiment, the penetration depthsab(0)=130(10) nm and c(0)=500 800 nm (parallel and perpendicular to the CuO2 planes, respectively) were extracted. Our results are compared with those obtained by other experimental techniques and theoretical predictions. © 1990 The American Physical Society.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Muon-spin-rotation (SR) experiments on a high-quality sintered YBa2Cu3Ox sample [x=6.970(1)] were performed, in order to obtain an accurate knowledge of the magnitude and the temperature dependence of the magnetic penetration depth in this copper oxide superconductor. Special attention was given to the data analysis. In particular, the systematic errors introduced by different types of analyses were estimated. Our results show that the temperature dependence of the effective penetration depth eff into the sintered sample is well described by the two-fluid model, with eff(0)=155(10) nm. This behavior of eff(T) is consistent with conventional s-wave pairing. With the anisotropy ratio cab=5(1) measured in a previous SR experiment, the penetration depthsab(0)=130(10) nm and c(0)=500 800 nm (parallel and perpendicular to the CuO2 planes, respectively) were extracted. Our results are compared with those obtained by other experimental techniques and theoretical predictions. © 1990 The American Physical Society.
1989
47.
T Williams, Y Maeno, I Mangelschots, A Reller, G Bednorz
Oxygen vacancy ordering in superconducting Nd2-xCexCuO4-y Journal Article
In: Physica C: Superconductivity and its applications, vol. 161, no. 3, pp. 331-344, 1989.
@article{Williams1989331,
title = {Oxygen vacancy ordering in superconducting Nd2-xCexCuO4-y},
author = {T Williams and Y Maeno and I Mangelschots and A Reller and G Bednorz},
doi = {10.1016/0921-4534(89)90344-4},
year = {1989},
date = {1989-01-01},
journal = {Physica C: Superconductivity and its applications},
volume = {161},
number = {3},
pages = {331-344},
abstract = {We report transmission electron microscopy results which show that an appreciable fraction of superconducting ceramic and single-crystal samples of the Nd2-xCexCuO4-y T' phase shows evidence for oxygen vacancies in the [Cu-O] planes which in some cases are ordered, either commensurately or incommensurately with the cation sublattice. As T' phase samples displaying a 100% Meissner signal are not yet available we cannot determine unambigously whether or not the oxygen loss is associated with superconduction but our results strongly suggest that supercell formation accompanying vacancy ordering occurs in over-reduced material which is no longer superconducting. © 1989.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
We report transmission electron microscopy results which show that an appreciable fraction of superconducting ceramic and single-crystal samples of the Nd2-xCexCuO4-y T' phase shows evidence for oxygen vacancies in the [Cu-O] planes which in some cases are ordered, either commensurately or incommensurately with the cation sublattice. As T' phase samples displaying a 100% Meissner signal are not yet available we cannot determine unambigously whether or not the oxygen loss is associated with superconduction but our results strongly suggest that supercell formation accompanying vacancy ordering occurs in over-reduced material which is no longer superconducting. © 1989.
46.
C Rossel, Y Maeno, I Morgenstern
Memory effects in a superconducting Y-Ba-Cu-O single crystal: A similarity to spin-glasses Journal Article
In: Physical Review Letters, vol. 62, no. 6, pp. 681-684, 1989.
@article{Rossel1989681,
title = {Memory effects in a superconducting Y-Ba-Cu-O single crystal: A similarity to spin-glasses},
author = {C Rossel and Y Maeno and I Morgenstern},
doi = {10.1103/PhysRevLett.62.681},
year = {1989},
date = {1989-01-01},
journal = {Physical Review Letters},
volume = {62},
number = {6},
pages = {681-684},
abstract = {We report on memory effects observed in the time dependence of the magnetization M(T, H) of a superconducting Y-Ba-Cu-O single crystal. As in spin-glasses, the decay rate S=dMdlnt is not uniquely determined. It exhibits a characteristic change at time t equal to the waiting time tw during which the specimen was kept at a given temperature T<Tc and magnetic field H before a field perturbation H is applied at time t=0. This phenomenon, seen for the first time in a superconductor, reveals the glassy nature of the superconducting state in the high-Tc oxides. © 1989 The American Physical Society.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
We report on memory effects observed in the time dependence of the magnetization M(T, H) of a superconducting Y-Ba-Cu-O single crystal. As in spin-glasses, the decay rate S=dMdlnt is not uniquely determined. It exhibits a characteristic change at time t equal to the waiting time tw during which the specimen was kept at a given temperature T<Tc and magnetic field H before a field perturbation H is applied at time t=0. This phenomenon, seen for the first time in a superconductor, reveals the glassy nature of the superconducting state in the high-Tc oxides. © 1989 The American Physical Society.
45.
Christophe Rossel, Yoshiteru Maeno, Frederic H Holtzberg
Memory effects in YBa2Cu3O7-δ single crystal Journal Article
In: IBM Journal of Research and Development, vol. 33, no. 3, pp. 328-332, 1989.
@article{Rossel1989328,
title = {Memory effects in YBa2Cu3O7-δ single crystal},
author = {Christophe Rossel and Yoshiteru Maeno and Frederic H Holtzberg},
doi = {10.1147/rd.333.0328},
year = {1989},
date = {1989-01-01},
journal = {IBM Journal of Research and Development},
volume = {33},
number = {3},
pages = {328-332},
abstract = {Measurements of the time dependence of zero-field-cooled (ZFC) and field-cooled (FC) magnetization M in YBa2Cu3O7-δ single crystal have been performed as a function of temperature and magnetic field. The appearance of an echo-like feature in the decay rate S = dM/d ln t at an observing time t equal to the waiting time tw during which the specimen was prepared at a given field H0 and temperature T reveals aging effects in the superconducting state. Similar phenomena reported in spin glasses seem to validate the picture of a superconducting glass state in YBa2Cu3O7-δ.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Measurements of the time dependence of zero-field-cooled (ZFC) and field-cooled (FC) magnetization M in YBa2Cu3O7-δ single crystal have been performed as a function of temperature and magnetic field. The appearance of an echo-like feature in the decay rate S = dM/d ln t at an observing time t equal to the waiting time tw during which the specimen was prepared at a given field H0 and temperature T reveals aging effects in the superconducting state. Similar phenomena reported in spin glasses seem to validate the picture of a superconducting glass state in YBa2Cu3O7-δ.
44.
K Satoh, T Fujita, Y Maeno
Low-Temperature Specific Heat of CexLa1&minus;xCu6 Journal Article
In: Journal of the Physical Society of Japan, vol. 58, no. 3, pp. 1012-1020, 1989.
@article{Satoh19891012,
title = {Low-Temperature Specific Heat of CexLa1−xCu6},
author = {K Satoh and T Fujita and Y Maeno},
doi = {10.1143/JPSJ.58.1012},
year = {1989},
date = {1989-01-01},
journal = {Journal of the Physical Society of Japan},
volume = {58},
number = {3},
pages = {1012-1020},
abstract = {Specific heat of a dense-Kondo system CexLa1-xCu6(x=0.0, 0.1, 0.3, 0.5, 0.9 and 1.0) has been measured systematically down to 0.1 K in various magnetic fields up to 5 T in order to clarify the transition from dilute- to dense-Kondo behavior and the nature of the heavy-fermion ground state. In zero field, the magnetic specific heat per molar Ce, Cm, increases as the Ce concentration decreases. This tendency is attributed to the decrease of the Kondo temperature caused by the ‘chemical expansion’ effect. In a magnetic field applied along the c-axis, Cm/T is strongly suppressed. The observed behavior ofCm/T is interpreted by using a ‘resonance model’ with the Lorent-zian density of states at the Fermi level, and for the dense system, CeCu6 the experiments suggest the development of the ‘dense’ effect below 2 T. © 1989, THE PHYSICAL SOCIETY OF JAPAN. All rights reserved.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Specific heat of a dense-Kondo system CexLa1-xCu6(x=0.0, 0.1, 0.3, 0.5, 0.9 and 1.0) has been measured systematically down to 0.1 K in various magnetic fields up to 5 T in order to clarify the transition from dilute- to dense-Kondo behavior and the nature of the heavy-fermion ground state. In zero field, the magnetic specific heat per molar Ce, Cm, increases as the Ce concentration decreases. This tendency is attributed to the decrease of the Kondo temperature caused by the ‘chemical expansion’ effect. In a magnetic field applied along the c-axis, Cm/T is strongly suppressed. The observed behavior ofCm/T is interpreted by using a ‘resonance model’ with the Lorent-zian density of states at the Fermi level, and for the dense system, CeCu6 the experiments suggest the development of the ‘dense’ effect below 2 T. © 1989, THE PHYSICAL SOCIETY OF JAPAN. All rights reserved.
43.
Y Maeno, F Lichitenberg, T Williams, J Kappinski, J G Bednorz
A new series of compounds in the T* structure:La2-x-zLnzSrxCuO4-y (Ln=Eu, Gd, Tb and Dy) Journal Article
In: Japanese Journal of Applied Physics, vol. 28, no. 6A, pp. L926-L929, 1989.
@article{Maeno1989L926,
title = {A new series of compounds in the T* structure:La2-x-zLnzSrxCuO4-y (Ln=Eu, Gd, Tb and Dy)},
author = {Y Maeno and F Lichitenberg and T Williams and J Kappinski and J G Bednorz},
doi = {10.1143/JJAP.28.L926},
year = {1989},
date = {1989-01-01},
journal = {Japanese Journal of Applied Physics},
volume = {28},
number = {6A},
pages = {L926-L929},
abstract = {We report the synthesis of a new seriesof layered copper-oxide compounds La2-x-zLnzSrxCuO4-y (Ln=Eu, Gd, Tb and Dy), which are isostructural to the T*-phase of superconductive Nd-Ce-Sr-Cu-O. Annealing in high-pressure oxygen atmosphere improves the metallic conductivity of the samples. However, we have not been able to induce bulk superconductivity in these new compounds. © 1989 The Japan Society of Applied Physics.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
We report the synthesis of a new seriesof layered copper-oxide compounds La2-x-zLnzSrxCuO4-y (Ln=Eu, Gd, Tb and Dy), which are isostructural to the T*-phase of superconductive Nd-Ce-Sr-Cu-O. Annealing in high-pressure oxygen atmosphere improves the metallic conductivity of the samples. However, we have not been able to induce bulk superconductivity in these new compounds. © 1989 The Japan Society of Applied Physics.
42.
H Fujii, T Inoue, Y Andoh, T Takabatake, K Satoh, Y Maeno, T Fujita, J Sakurai, Y Yamaguchi
Anisotropic Kondo effect in a valence-fluctuating system: CeNiIn Journal Article
In: Physical Review B, vol. 39, no. 10, pp. 6840-6843, 1989.
@article{Fujii19896840,
title = {Anisotropic Kondo effect in a valence-fluctuating system: CeNiIn},
author = {H Fujii and T Inoue and Y Andoh and T Takabatake and K Satoh and Y Maeno and T Fujita and J Sakurai and Y Yamaguchi},
doi = {10.1103/PhysRevB.39.6840},
year = {1989},
date = {1989-01-01},
journal = {Physical Review B},
volume = {39},
number = {10},
pages = {6840-6843},
abstract = {Measurements of magnetic susceptibility, electrical resistivity, thermoelectric power, and thermal expansion have been made on CeNiIn single crystals with a hexagonal Fe2P-type structure. The results indicate that CeNiIn is a valence-fluctuating system with a significantly anisotropic Kondo effect which comes from anisotropic c-f mixing along the a and c axes. Specific-heat measurements on a CeNiIn polycrystal sample reveal that the magnetic contribution divided by temperature Cm/T takes a minimum around 20 K and reaches 60 mJ/K2 mole around T=2 K, which is still ten times larger than that of LaNiIn with no 4f electron © 1989 The American Physical Society.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Measurements of magnetic susceptibility, electrical resistivity, thermoelectric power, and thermal expansion have been made on CeNiIn single crystals with a hexagonal Fe2P-type structure. The results indicate that CeNiIn is a valence-fluctuating system with a significantly anisotropic Kondo effect which comes from anisotropic c-f mixing along the a and c axes. Specific-heat measurements on a CeNiIn polycrystal sample reveal that the magnetic contribution divided by temperature Cm/T takes a minimum around 20 K and reaches 60 mJ/K2 mole around T=2 K, which is still ten times larger than that of LaNiIn with no 4f electron © 1989 The American Physical Society.
41.
B Pümpin, H Keller, W Kündig, W Odermatt, I M Savić, J W Schneider, H Simmler, P Zimmermann, J G Bednorz, Y Maeno, K A Müller, C Rossel, E Kaldis, S Rusiecki, W Assmus, J Kowalewski
Measurement of the London penetration depths in YBa2Cu3Ox by means of muon spin rotation (μSR) experiments Journal Article
In: Physica C: Superconductivity and its applications, vol. 162-164, no. PART 1, pp. 151-152, 1989.
@article{Pümpin1989151,
title = {Measurement of the London penetration depths in YBa2Cu3Ox by means of muon spin rotation (μSR) experiments},
author = {B Pümpin and H Keller and W Kündig and W Odermatt and I M Savić and J W Schneider and H Simmler and P Zimmermann and J G Bednorz and Y Maeno and K A Müller and C Rossel and E Kaldis and S Rusiecki and W Assmus and J Kowalewski},
doi = {10.1016/0921-4534(89)90962-3},
year = {1989},
date = {1989-01-01},
journal = {Physica C: Superconductivity and its applications},
volume = {162-164},
number = {PART 1},
pages = {151-152},
abstract = {To get accurate values of the London penetration depths in YBa2Cu3Ox, μSR measurements were performed on a high quality, sintered sample and a c-axis-oriented polycrystal. For the sintered sample the temperature dependence of the effective penetration depth λeff is well described by the two-fluid model, with λeff(0) = 155(10) nm. This behavior of λeff(T) is consistent with conventional s-wave pairing. The anisotropy ratio λc λab reversed tilde equals 5(1) was determined from measurements on the polycrystal. These results were used to calculate λab(0) = 130(10) nm and λc(0) reversed tilde equals 500 - 800 nm. © 1989.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
To get accurate values of the London penetration depths in YBa2Cu3Ox, μSR measurements were performed on a high quality, sintered sample and a c-axis-oriented polycrystal. For the sintered sample the temperature dependence of the effective penetration depth λeff is well described by the two-fluid model, with λeff(0) = 155(10) nm. This behavior of λeff(T) is consistent with conventional s-wave pairing. The anisotropy ratio λc λab reversed tilde equals 5(1) was determined from measurements on the polycrystal. These results were used to calculate λab(0) = 130(10) nm and λc(0) reversed tilde equals 500 - 800 nm. © 1989.
1988
40.
T Fujita, K Satoh, Y Maeno, Y Uwatoko, H Fujii
Specific heat of a dense-Kondo compound CePtIn Journal Article
In: Journal of Magnetism and Magnetic Materials, vol. 76-77, no. C, pp. 133-134, 1988.
@article{Fujita1988133,
title = {Specific heat of a dense-Kondo compound CePtIn},
author = {T Fujita and K Satoh and Y Maeno and Y Uwatoko and H Fujii},
doi = {10.1016/0304-8853(88)90340-X},
year = {1988},
date = {1988-01-01},
journal = {Journal of Magnetism and Magnetic Materials},
volume = {76-77},
number = {C},
pages = {133-134},
abstract = {Specific heat of a newly-found dense-Kondo compound CePtIn was measured between 60 mK and 80 K. Below 8 K, the ratio C/T remarkably increases, suggesting the heavy-fermion nature of this compound. There is no sign of any phase transition at least down to 50 mK. © 1988.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Specific heat of a newly-found dense-Kondo compound CePtIn was measured between 60 mK and 80 K. Below 8 K, the ratio C/T remarkably increases, suggesting the heavy-fermion nature of this compound. There is no sign of any phase transition at least down to 50 mK. © 1988.
39.
K Satoh, T Fujita, Y Maeno, Y Onuki, T Komatsubara
Low-temperature specific heat of CexLa1-xCu6 in magnetic field Journal Article
In: Journal of Magnetism and Magnetic Materials, vol. 76-77, no. C, pp. 128-130, 1988.
@article{Satoh1988128,
title = {Low-temperature specific heat of CexLa1-xCu6 in magnetic field},
author = {K Satoh and T Fujita and Y Maeno and Y Onuki and T Komatsubara},
doi = {10.1016/0304-8853(88)90338-1},
year = {1988},
date = {1988-01-01},
journal = {Journal of Magnetism and Magnetic Materials},
volume = {76-77},
number = {C},
pages = {128-130},
abstract = {The specific heat of the heavy-fermion system CexLa1-xCu6 has been measured between 0.1 and 2 K in magnetic fields up to 5 T. In low field, the zero-temperature value γ0 = (Cm/T)T = 0 for CeCu6 shows deviations from behavior for dilute systems suggesting some correlation between 4f electrons. © 1988.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
The specific heat of the heavy-fermion system CexLa1-xCu6 has been measured between 0.1 and 2 K in magnetic fields up to 5 T. In low field, the zero-temperature value γ0 = (Cm/T)T = 0 for CeCu6 shows deviations from behavior for dilute systems suggesting some correlation between 4f electrons. © 1988.
38.
M Kurisu, K Kumagai, Y Maeno, T Fujita
In: Physica C: Superconductivity and its applications, vol. 152, no. 4, pp. 339-344, 1988.
@article{Kurisu1988339,
title = {Pressure dependences of superconducting transition temperature Tc in orthorhombic and impurity-induced tetragonal YBa2(Cu1-xMx)3O7-y (M=Fe, Co, Ni and Zn)},
author = {M Kurisu and K Kumagai and Y Maeno and T Fujita},
doi = {10.1016/0921-4534(88)90093-7},
year = {1988},
date = {1988-01-01},
journal = {Physica C: Superconductivity and its applications},
volume = {152},
number = {4},
pages = {339-344},
abstract = {The pressure dependences of the superconducting transition temperature Tc of both orthorhombic and impurity-induced tetragonal YBa2(Cu1-xMx)3O7-y (M=Fe, Co, Ni and Zn) are studied by electrical resistance measurements under hydrostatic pressure up to 30 kbar. A strong correlation between the pressure dependence of Tc and the crystal structure is found: the rate of pressure enhancement of Tc, dTc/dP, is four times larger for the tretragonal phase than for the orthorhombic phase; neither the choice of the dopant, the amount of doping x, nor the magnitude of Tc at P=O kbar is the major factor to determine the pressure effect of Tc. © 1988.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
The pressure dependences of the superconducting transition temperature Tc of both orthorhombic and impurity-induced tetragonal YBa2(Cu1-xMx)3O7-y (M=Fe, Co, Ni and Zn) are studied by electrical resistance measurements under hydrostatic pressure up to 30 kbar. A strong correlation between the pressure dependence of Tc and the crystal structure is found: the rate of pressure enhancement of Tc, dTc/dP, is four times larger for the tretragonal phase than for the orthorhombic phase; neither the choice of the dopant, the amount of doping x, nor the magnitude of Tc at P=O kbar is the major factor to determine the pressure effect of Tc. © 1988.
37.
M Kato, Y Maeno, T Fujita
Variation of temperature-linear specific heat with doping in (La1-xSrx)2CuO4 Journal Article
In: Physica C: Superconductivity and its applications, vol. 152, no. 1, pp. 116-120, 1988.
@article{Kato1988116,
title = {Variation of temperature-linear specific heat with doping in (La1-xSrx)2CuO4},
author = {M Kato and Y Maeno and T Fujita},
doi = {10.1016/0921-4534(88)90080-9},
year = {1988},
date = {1988-01-01},
journal = {Physica C: Superconductivity and its applications},
volume = {152},
number = {1},
pages = {116-120},
abstract = {Low-temperature specific heat of (La1-xSrx)2CuO4 has been studied between 2 and 20 K by systematically varying the Sr concentration x, in order to clarify the origin of non-zero γ, the temperature-linear specific-heat coefficient, frequently observed in high-Tc superconducting oxides. Identical procedure is used to prepare samples for the specific-heat measurement and for the determination of the structural, magnetic and superconductive phase-transition temperatures as a function of x. The value of γ is nearly zero in the antiferromagnetic ordering region, but increase abruptly with x to about 4 mJ/K2 mol in the insulating, but not antiferromagnetic region. By increasing x further into the superconductive region, γ tends to be smaller: 1.6 mJ/K2mol for x = 0.075. We argue that the non-zero γ is not due to inhomogeneity of the samples, but due to electronic origin intrinsic to this system. © 1988.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Low-temperature specific heat of (La1-xSrx)2CuO4 has been studied between 2 and 20 K by systematically varying the Sr concentration x, in order to clarify the origin of non-zero γ, the temperature-linear specific-heat coefficient, frequently observed in high-Tc superconducting oxides. Identical procedure is used to prepare samples for the specific-heat measurement and for the determination of the structural, magnetic and superconductive phase-transition temperatures as a function of x. The value of γ is nearly zero in the antiferromagnetic ordering region, but increase abruptly with x to about 4 mJ/K2 mol in the insulating, but not antiferromagnetic region. By increasing x further into the superconductive region, γ tends to be smaller: 1.6 mJ/K2mol for x = 0.075. We argue that the non-zero γ is not due to inhomogeneity of the samples, but due to electronic origin intrinsic to this system. © 1988.
36.
Y Maeno, T Fujita
Effects of substitution for copper in high-Tc oxides Journal Article
In: Physica C: Superconductivity and its Applications, vol. 153-155, pp. 1105-1110, 1988.
@article{Maeno19881105,
title = {Effects of substitution for copper in high-Tc oxides},
author = {Y Maeno and T Fujita},
doi = {10.1016/0921-4534(88)90210-9},
year = {1988},
date = {1988-01-01},
journal = {Physica C: Superconductivity and its Applications},
volume = {153-155},
pages = {1105-1110},
abstract = {A variety of phenomena induced by transition metal and other metal substitution for copper in high-Tc oxides are discussed. In YBa2(Cu1−xMx)3O7−y a structural change from orthorhombic to tetragonal occurs for M = Fe, Co and Ga with increasing x. Bulk superconductivity in the impurity-induced tetragonal phase with Tc over 80 K suggests that long-range ordering of one-dimensional Cu-O chains is not crucially required for superconductivity. Thermogravimetric analysis and X-ray diffraction at high temperatures for M = Fe show that the amount of oxygen contained at high temperature increases significantly and non-linearly with x. Distribution of Fe in the two inequivalent Cu sites are controlled reversiblly by a systematic heat treatment, and the change in superconducting properties are studied, including the effect of pressure up to 30 kbar. © 1988, Elsevier Science Publishers B.V.. All rights reserved.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
A variety of phenomena induced by transition metal and other metal substitution for copper in high-Tc oxides are discussed. In YBa2(Cu1−xMx)3O7−y a structural change from orthorhombic to tetragonal occurs for M = Fe, Co and Ga with increasing x. Bulk superconductivity in the impurity-induced tetragonal phase with Tc over 80 K suggests that long-range ordering of one-dimensional Cu-O chains is not crucially required for superconductivity. Thermogravimetric analysis and X-ray diffraction at high temperatures for M = Fe show that the amount of oxygen contained at high temperature increases significantly and non-linearly with x. Distribution of Fe in the two inequivalent Cu sites are controlled reversiblly by a systematic heat treatment, and the change in superconducting properties are studied, including the effect of pressure up to 30 kbar. © 1988, Elsevier Science Publishers B.V.. All rights reserved.
35.
S Noguchi, J Inoue, K Okuda, Y Maeno, T Fujita
Magnetic Susceptibility of Fe-Doped YBa2Cu3O7-δ Journal Article
In: Japanese Journal of Applied Physics, vol. 27, no. 3A, pp. L390-L392, 1988.
@article{Noguchi1988L390,
title = {Magnetic Susceptibility of Fe-Doped YBa2Cu3O7-δ},
author = {S Noguchi and J Inoue and K Okuda and Y Maeno and T Fujita},
doi = {10.1143/JJAP.27.L390},
year = {1988},
date = {1988-01-01},
journal = {Japanese Journal of Applied Physics},
volume = {27},
number = {3A},
pages = {L390-L392},
abstract = {Magnetic properties of YBa2(Cu1-xFex)3O7-δwith 0≦x≦0.085 were investigated by dc- and ac-magnetic susceptibility in a temperature range from 4.2 to 300 K. The susceptibility in the normal state follows the Curie-Weisslaw χ=C/(T-⊝)+χ0with constant paramagnetism χ0The effective magnetic moments estimated from the Curie constant are 3.4∽4.0 μBFe, which are consistent with the magnetic moment obtained in the Mössbauer experiments. From the ac susceptibility in the superconducting state, a decrease of volume fraction of superconductivity was observed with increasing Fe-concentration. © 1988 The Japan Society of Applied Physics.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Magnetic properties of YBa2(Cu1-xFex)3O7-δwith 0≦x≦0.085 were investigated by dc- and ac-magnetic susceptibility in a temperature range from 4.2 to 300 K. The susceptibility in the normal state follows the Curie-Weisslaw χ=C/(T-⊝)+χ0with constant paramagnetism χ0The effective magnetic moments estimated from the Curie constant are 3.4∽4.0 μBFe, which are consistent with the magnetic moment obtained in the Mössbauer experiments. From the ac susceptibility in the superconducting state, a decrease of volume fraction of superconductivity was observed with increasing Fe-concentration. © 1988 The Japan Society of Applied Physics.
34.
T Tamaki, T Komai, A Ito, Y Maeno, T Fujita
Mössbauer study of YBa2 (Cu1-xFex)3O7-δ : Superconductivity and magnetic order Journal Article
In: Solid State Communications, vol. 65, no. 1, pp. 43-46, 1988.
@article{Tamaki198843,
title = {Mössbauer study of YBa2 (Cu1-xFex)3O7-δ : Superconductivity and magnetic order},
author = {T Tamaki and T Komai and A Ito and Y Maeno and T Fujita},
doi = {10.1016/0038-1098(88)90584-4},
year = {1988},
date = {1988-01-01},
journal = {Solid State Communications},
volume = {65},
number = {1},
pages = {43-46},
abstract = {The electronic and magnetic properties of the ceramic superconductor YBa2 (Cu1-xFex)3O7-δ with x =0.010, 0.017, 0.033 and 0.067 have been studied microscopically by Mössbauer technique. We have shown that Fe's are substituted for both Cu 1 and Cu 2 sites. We have also shown that the samples with x >; 0.01 undergo a magnetic transition at low temperatures without destroying the superconductivity, and that the magnetic transition temperature TM increases with x. The coexistence of the superconductivity and the magnetic order is discussed, and it is argued that spin fluctuations of Cu are related to the superconductivity. © 1988.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
The electronic and magnetic properties of the ceramic superconductor YBa2 (Cu1-xFex)3O7-δ with x =0.010, 0.017, 0.033 and 0.067 have been studied microscopically by Mössbauer technique. We have shown that Fe's are substituted for both Cu 1 and Cu 2 sites. We have also shown that the samples with x >; 0.01 undergo a magnetic transition at low temperatures without destroying the superconductivity, and that the magnetic transition temperature TM increases with x. The coexistence of the superconductivity and the magnetic order is discussed, and it is argued that spin fluctuations of Cu are related to the superconductivity. © 1988.
33.
T Fujiwara, H Nakata, T Kumamaru, Y Maeno, Y Aoki, T Fujita
Thermal analysis of YBa2(Cu1-xFex)3O7-y oxide superconductor Journal Article
In: Chemistry Letters, vol. 17, no. 9, pp. 1527-1530, 1988.
@article{Fujiwara19881527,
title = {Thermal analysis of YBa2(Cu1-xFex)3O7-y oxide superconductor},
author = {T Fujiwara and H Nakata and T Kumamaru and Y Maeno and Y Aoki and T Fujita},
year = {1988},
date = {1988-01-01},
journal = {Chemistry Letters},
volume = {17},
number = {9},
pages = {1527-1530},
abstract = {Thermogravimetry and powder X-ray diffraction measurements have been made for the title superconductors to show a marked discontinuity in the slope of oxygen content vs. c cell dimension plots at 810°C (T2), other than at about 400°C (T1). The oxygen content at T2 increases with increasing Fe doping content. © 1988 The Chemical Society of Japan.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Thermogravimetry and powder X-ray diffraction measurements have been made for the title superconductors to show a marked discontinuity in the slope of oxygen content vs. c cell dimension plots at 810°C (T2), other than at about 400°C (T1). The oxygen content at T2 increases with increasing Fe doping content. © 1988 The Chemical Society of Japan.
1987
32.
Y Maeno, M Kato, T Fujita
Preparation of Y-Ba-Cu oxides with superconducting transition above liquid-nitrogen temperature Journal Article
In: Japanese Journal of Applied Physics, vol. 26, no. 4 A, pp. L329-L331, 1987.
@article{Maeno1987L329,
title = {Preparation of Y-Ba-Cu oxides with superconducting transition above liquid-nitrogen temperature},
author = {Y Maeno and M Kato and T Fujita},
doi = {10.1143/JJAP.26.L329},
year = {1987},
date = {1987-01-01},
journal = {Japanese Journal of Applied Physics},
volume = {26},
number = {4 A},
pages = {L329-L331},
abstract = {Details of sample preparation of Y-Ba-Cu oxides with superconducting transition temperatures well above the boiling point of liquid nitrogen are reported. The mid-point of the resistive transition is at 92.6 K , and the zero-resistance state is maintained up to 83.3 K. The ac susceptibility and the infrared spectra of superconductive Y-Ba-Cu oxides are also presented. © 1987 IOP Publishing Ltd.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Details of sample preparation of Y-Ba-Cu oxides with superconducting transition temperatures well above the boiling point of liquid nitrogen are reported. The mid-point of the resistive transition is at 92.6 K , and the zero-resistance state is maintained up to 83.3 K. The ac susceptibility and the infrared spectra of superconductive Y-Ba-Cu oxides are also presented. © 1987 IOP Publishing Ltd.
31.
Y Maeno, M Kato, Y Aoki, T Fujita
Superconductivity in impurity-induced tetragonal YBa2(Cu1-xFex)3O7-δ Journal Article
In: Japanese Journal of Applied Physics, vol. 26, no. 12 A, pp. L1982-L1984, 1987.
@article{Maeno1987L1982,
title = {Superconductivity in impurity-induced tetragonal YBa2(Cu1-xFex)3O7-δ},
author = {Y Maeno and M Kato and Y Aoki and T Fujita},
doi = {10.1143/JJAP.26.L1982},
year = {1987},
date = {1987-01-01},
journal = {Japanese Journal of Applied Physics},
volume = {26},
number = {12 A},
pages = {L1982-L1984},
abstract = {Lattice deformation and superconductivity in YBa2(Cu1-xFex)3O7-δ are studied in detail. An orthorhombic to tetragonal phase change is induced at xc≈0.02. A phase diagram in the temperature-concentration plane clarifies two regions of the tetragonal phase: one is, as known previously, induced mainly by the release of oxygen, and the other by the direct action of impurities. Bulk nature of superconductivity in the novel impurity-induced tetragonal phase is confirmed by magnetic susceptibility measurements. © 1987 IOP Publishing Ltd.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Lattice deformation and superconductivity in YBa2(Cu1-xFex)3O7-δ are studied in detail. An orthorhombic to tetragonal phase change is induced at xc≈0.02. A phase diagram in the temperature-concentration plane clarifies two regions of the tetragonal phase: one is, as known previously, induced mainly by the release of oxygen, and the other by the direct action of impurities. Bulk nature of superconductivity in the novel impurity-induced tetragonal phase is confirmed by magnetic susceptibility measurements. © 1987 IOP Publishing Ltd.
30.
Y Maeno, M Kato, Y Aoki, T Nojima, T Fujita
Superconductivity in modified systems based on YBa2Cu3O7-δ Journal Article
In: Physica B+C, vol. 148, no. 1-3, pp. 357-359, 1987.
@article{Maeno1987357,
title = {Superconductivity in modified systems based on YBa2Cu3O7-δ},
author = {Y Maeno and M Kato and Y Aoki and T Nojima and T Fujita},
doi = {10.1016/0378-4363(87)90233-6},
year = {1987},
date = {1987-01-01},
journal = {Physica B+C},
volume = {148},
number = {1-3},
pages = {357-359},
abstract = {In order to study the impurity effects and the different role each of the two distinctive Cu sites plays, superconductivity in YBa2(Cu1-xMx)3O7-δ was investigated with various 3d and other elements M substituted for Cu. An orthorhombic to tetragonal phase transition is induced by M = Fe, Co and Ga. With M = Fe, it is induced at xc ≈ 0.02 at room temperature. The resistivity and magnetic susceptibility measurements support the bulk nature of superconductivity in the impurity-induced tetragonal phase. © 1987.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
In order to study the impurity effects and the different role each of the two distinctive Cu sites plays, superconductivity in YBa2(Cu1-xMx)3O7-δ was investigated with various 3d and other elements M substituted for Cu. An orthorhombic to tetragonal phase transition is induced by M = Fe, Co and Ga. With M = Fe, it is induced at xc ≈ 0.02 at room temperature. The resistivity and magnetic susceptibility measurements support the bulk nature of superconductivity in the impurity-induced tetragonal phase. © 1987.
29.
M Kurisu, H Kadomatsu, H Fujiwara, Y Maeno, T Fujita
Effect of hydrostatic pressure on the superconducting transition temperature of La1xBax2CuO4-y with x=0.075 Journal Article
In: Japanese Journal of Applied Physics, vol. 26, no. 4 A, pp. L361-L362, 1987.
@article{Kurisu1987L361,
title = {Effect of hydrostatic pressure on the superconducting transition temperature of La1xBax2CuO4-y with x=0.075},
author = {M Kurisu and H Kadomatsu and H Fujiwara and Y Maeno and T Fujita},
doi = {10.1143/JJAP.26.L361},
year = {1987},
date = {1987-01-01},
journal = {Japanese Journal of Applied Physics},
volume = {26},
number = {4 A},
pages = {L361-L362},
abstract = {The pressure dependence of superconducting transition temperature Tc of La1-xBax2CuO4-y with x=0.075 was determined under hydrostatic pressure up to 20 kbar. It is found that Tc linearly increases and the width of transition is broadened with pressure. The pressure enhancement of Tc is interpreted as being a support for the suggestion that Tc is correlated with the copper-oxygen distance. © 1987 IOP Publishing Ltd.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
The pressure dependence of superconducting transition temperature Tc of La1-xBax2CuO4-y with x=0.075 was determined under hydrostatic pressure up to 20 kbar. It is found that Tc linearly increases and the width of transition is broadened with pressure. The pressure enhancement of Tc is interpreted as being a support for the suggestion that Tc is correlated with the copper-oxygen distance. © 1987 IOP Publishing Ltd.
28.
Y Maeno, Y Aoki, H Kamimura, J Sakurai, T Fujita
Transport Properties and Specific Heat of (La1-xBax)2CuO4-y Journal Article
In: Japanese Journal of Applied Physics, vol. 26, no. 4 A, pp. L402-L404, 1987.
@article{Maeno1987L402,
title = {Transport Properties and Specific Heat of (La1-xBax)2CuO4-y},
author = {Y Maeno and Y Aoki and H Kamimura and J Sakurai and T Fujita},
doi = {10.1143/JJAP.26.L402},
year = {1987},
date = {1987-01-01},
journal = {Japanese Journal of Applied Physics},
volume = {26},
number = {4 A},
pages = {L402-L404},
abstract = {X-ray analysis, covering a wide temperature range between 10 and 300 K, and the measurements of the thermoelectric power and specific heat are performed on a recently discovered high-Tc superconductor, (La1-xBax)2CuO4-y with x=0.075. A large positive thermoelectric power is observed above Tc. The Debye temperature is 385 K and no specificheat jump is detected across Tc. © 1987 IOP Publishing Ltd.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
X-ray analysis, covering a wide temperature range between 10 and 300 K, and the measurements of the thermoelectric power and specific heat are performed on a recently discovered high-Tc superconductor, (La1-xBax)2CuO4-y with x=0.075. A large positive thermoelectric power is observed above Tc. The Debye temperature is 385 K and no specificheat jump is detected across Tc. © 1987 IOP Publishing Ltd.
27.
Y Maeno, M Takahashi, T Fujita, Y Uwatoko, H Fujii, T Okamoto
Specific heat of a new dense-kondo compound cepdin Journal Article
In: Japanese Journal of Applied Physics, vol. 26, no. S3-1, pp. 545-546, 1987.
@article{Maeno1987545,
title = {Specific heat of a new dense-kondo compound cepdin},
author = {Y Maeno and M Takahashi and T Fujita and Y Uwatoko and H Fujii and T Okamoto},
doi = {10.7567/JJAPS.26S3.545},
year = {1987},
date = {1987-01-01},
journal = {Japanese Journal of Applied Physics},
volume = {26},
number = {S3-1},
pages = {545-546},
abstract = {The specific heat of a newly-found dense-Kondo compound, CePdIn, has been measured between 1.8 and 80 K. The magnetic contribution to the specific heat},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
The specific heat of a newly-found dense-Kondo compound, CePdIn, has been measured between 1.8 and 80 K. The magnetic contribution to the specific heat
26.
K Satoh, M Kato, Y Maeno, T Fujita, Y Onuki, T Komatsubara
Concentration dependence of specific heat of cexla1-xcu6 Journal Article
In: Japanese Journal of Applied Physics, vol. 26, no. S3-1, pp. 521-522, 1987.
@article{Satoh1987521,
title = {Concentration dependence of specific heat of cexla1-xcu6},
author = {K Satoh and M Kato and Y Maeno and T Fujita and Y Onuki and T Komatsubara},
doi = {10.7567/JJAPS.26S3.521},
year = {1987},
date = {1987-01-01},
journal = {Japanese Journal of Applied Physics},
volume = {26},
number = {S3-1},
pages = {521-522},
abstract = {Specific heat of a dense-Kondo system CexLa1-xCu6 has been measured systematically down to 0.1 K. With decreasing the Ce concentration, the specfic heat per molar Ce increases and the Kondo temperature is found to decrease. Also the results are reasonably compared with theories for the dilute-Kondo system. © 1987 The Japan Society of Applied Physics.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Specific heat of a dense-Kondo system CexLa1-xCu6 has been measured systematically down to 0.1 K. With decreasing the Ce concentration, the specfic heat per molar Ce increases and the Kondo temperature is found to decrease. Also the results are reasonably compared with theories for the dilute-Kondo system. © 1987 The Japan Society of Applied Physics.
25.
K Ohbayashi, N Ogita, M Udagawa, Y Aoki, Y Maeno, T Fujita
Infrared and raman spectroscopy of high Tc superconducting system (La1-xBax)2CuO4 Journal Article
In: Japanese Journal of Applied Physics, vol. 26, no. 4 A, pp. L420-L422, 1987.
@article{Ohbayashi1987L420,
title = {Infrared and raman spectroscopy of high Tc superconducting system (La1-xBax)2CuO4},
author = {K Ohbayashi and N Ogita and M Udagawa and Y Aoki and Y Maeno and T Fujita},
doi = {10.1143/JJAP.26.L420},
year = {1987},
date = {1987-01-01},
journal = {Japanese Journal of Applied Physics},
volume = {26},
number = {4 A},
pages = {L420-L422},
abstract = {Infrared absorption spectra of (La1-xBax)2CuO4-y; (x=0, 0.02, 0.03, 0.04, 0.06, 0.075, 0.10, 0.15 and 0.20) have been measured at room temperature between the energy region from 400 to 4000 cm-1. The phonon spectra have been found to change sensitively with the change in concentration. The spectral shape has been found to show good correspondence to the crystal structure. The absorption edge of some electrical transition has been clearly observed at all compositions. The energy gap corresponding to this absorption edge has been found to be almost independent of the concentration. © 1987 IOP Publishing Ltd.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Infrared absorption spectra of (La1-xBax)2CuO4-y; (x=0, 0.02, 0.03, 0.04, 0.06, 0.075, 0.10, 0.15 and 0.20) have been measured at room temperature between the energy region from 400 to 4000 cm-1. The phonon spectra have been found to change sensitively with the change in concentration. The spectral shape has been found to show good correspondence to the crystal structure. The absorption edge of some electrical transition has been clearly observed at all compositions. The energy gap corresponding to this absorption edge has been found to be almost independent of the concentration. © 1987 IOP Publishing Ltd.
24.
K Ohbayashi, N Ogita, M Udagawa, Y Aoki, Y Maeno, T Fujita
Temperature dependence of infrared spectra of (La1-xBax)2CuO4-y Journal Article
In: Japanese Journal of Applied Physics, vol. 26, no. 4 A, pp. L423-L425, 1987.
@article{Ohbayashi1987L423,
title = {Temperature dependence of infrared spectra of (La1-xBax)2CuO4-y},
author = {K Ohbayashi and N Ogita and M Udagawa and Y Aoki and Y Maeno and T Fujita},
doi = {10.1143/JJAP.26.L423},
year = {1987},
date = {1987-01-01},
journal = {Japanese Journal of Applied Physics},
volume = {26},
number = {4 A},
pages = {L423-L425},
abstract = {Temperature dependence of the infrared spectra of (La1-xBax)2CuO4-y (x=0, 0.02, 0.06, 0.10, 0.20) have been measured in the energy region between 400 and 800 cm-1. For x=0 and 0.02, the crystal structure is orthorhombic at room temperature and becomes tetragonal (Tt phase) at elevated temperature. For x=0.06, 0.10 and 0.20, the crystal structure is tetragonal (Tx phase). It has been found that the infrared spectra are different for the Tt phase and the Tx phase. From the difference of the infrared spectra and the similarity of the X-ray diffraction patterns, the Tt phase is concluded to be of the K2NiF4 type and the Tx phase is expected to be of the Nd2CuO4 type. © 1987 IOP Publishing Ltd.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Temperature dependence of the infrared spectra of (La1-xBax)2CuO4-y (x=0, 0.02, 0.06, 0.10, 0.20) have been measured in the energy region between 400 and 800 cm-1. For x=0 and 0.02, the crystal structure is orthorhombic at room temperature and becomes tetragonal (Tt phase) at elevated temperature. For x=0.06, 0.10 and 0.20, the crystal structure is tetragonal (Tx phase). It has been found that the infrared spectra are different for the Tt phase and the Tx phase. From the difference of the infrared spectra and the similarity of the X-ray diffraction patterns, the Tt phase is concluded to be of the K2NiF4 type and the Tx phase is expected to be of the Nd2CuO4 type. © 1987 IOP Publishing Ltd.
23.
T Fujita, Y Aoki, Y Maeno, J Sakurai, H Fukuba, H Fujii
Crystallographic, magnetic, and superconductive transitions in (La1-xBax)2CuO4-y Journal Article
In: Japanese Journal of Applied Physics, vol. 26, no. 4 A, pp. L368-L370, 1987.
@article{Fujita1987L368,
title = {Crystallographic, magnetic, and superconductive transitions in (La1-xBax)2CuO4-y},
author = {T Fujita and Y Aoki and Y Maeno and J Sakurai and H Fukuba and H Fujii},
doi = {10.1143/JJAP.26.L368},
year = {1987},
date = {1987-01-01},
journal = {Japanese Journal of Applied Physics},
volume = {26},
number = {4 A},
pages = {L368-L370},
abstract = {Three types of phase transitions in (La1-xBax)2CuO4-y–orthorhombic to tetragonal, spin density wave (SDW) and superconductive–were traced as a function of the Ba concentration, x. The obtained phase diagram indicates that the SDW state does not coexist with superconductivity, whereas samples both in orthorhombic and tetragonal phases can be superconducting. © 1987 IOP Publishing Ltd.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Three types of phase transitions in (La1-xBax)2CuO4-y–orthorhombic to tetragonal, spin density wave (SDW) and superconductive–were traced as a function of the Ba concentration, x. The obtained phase diagram indicates that the SDW state does not coexist with superconductivity, whereas samples both in orthorhombic and tetragonal phases can be superconducting. © 1987 IOP Publishing Ltd.
22.
N Ogita, K Ohbayashi, M Udagawa, Y Aoki, Y Maeno, T Fujita
Infrared spectroscopy of (La1-xMx)2CuO4-y; M=Sr, Ba, K and Ce Journal Article
In: Japanese Journal of Applied Physics, vol. 26, no. 4 A, pp. L415-L446, 1987.
@article{Ogita1987L415,
title = {Infrared spectroscopy of (La1-xMx)2CuO4-y; M=Sr, Ba, K and Ce},
author = {N Ogita and K Ohbayashi and M Udagawa and Y Aoki and Y Maeno and T Fujita},
doi = {10.1143/JJAP.26.L415},
year = {1987},
date = {1987-01-01},
journal = {Japanese Journal of Applied Physics},
volume = {26},
number = {4 A},
pages = {L415-L446},
abstract = {Infrared absorption spectra have been measured at room temperature for samples (La0.9Sr0.1)2CuO4-y, (La0.925Ba0.075)2CuO4-y, (La0.95K0.05)2CuO4-y and (La0.9Ce0.1)2CuO4-y. Good correspondence between the superconductivity and the infrared spectrum has been observed. © 1987 IOP Publishing Ltd.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Infrared absorption spectra have been measured at room temperature for samples (La0.9Sr0.1)2CuO4-y, (La0.925Ba0.075)2CuO4-y, (La0.95K0.05)2CuO4-y and (La0.9Ce0.1)2CuO4-y. Good correspondence between the superconductivity and the infrared spectrum has been observed. © 1987 IOP Publishing Ltd.
21.
M Kato, K Satoh, Y Maeno, Y Aoki, T Fujita, Y Onuki, T Komatsubara
Specific Heat of a Dense-Kondo System CexLa1-xCu6 Journal Article
In: Journal of the Physical Society of Japan, vol. 56, no. 10, pp. 3661-3666, 1987.
@article{Kato19873661,
title = {Specific Heat of a Dense-Kondo System CexLa1-xCu6},
author = {M Kato and K Satoh and Y Maeno and Y Aoki and T Fujita and Y Onuki and T Komatsubara},
doi = {10.1143/JPSJ.56.3661},
year = {1987},
date = {1987-01-01},
journal = {Journal of the Physical Society of Japan},
volume = {56},
number = {10},
pages = {3661-3666},
abstract = {Specific heat of a dense-Kondo system, CexLa1-xCu6, has been systematically measured between 2 and 80 K in order to clarify the transition from dilute-Kondo to dense-Kondo behavior as the cerium concentration, x, increases. We have found that the magnetic specific heat per molar cerium, Cm, is nearly independent of x and is explained by a simple sum of the Kondo specific heat and the Schottky specific heat, with the x-independent energy separation between the ground and the first excited states (65 K). However, due to the interaction between the cerium ions, the first excited state tends to be broadened as x increases, and the width of the first excited state for the dense limit of CeCu6 (TK=3.9 K) is estimated to be about 20 K. At low temperatures, Cm increases as x is decreased. This tendency is qualitatively interpreted as due to the decrease in TK caused by the increase of unit cell volume. © 1987, THE PHYSICAL SOCIETY OF JAPAN. All rights reserved.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Specific heat of a dense-Kondo system, CexLa1-xCu6, has been systematically measured between 2 and 80 K in order to clarify the transition from dilute-Kondo to dense-Kondo behavior as the cerium concentration, x, increases. We have found that the magnetic specific heat per molar cerium, Cm, is nearly independent of x and is explained by a simple sum of the Kondo specific heat and the Schottky specific heat, with the x-independent energy separation between the ground and the first excited states (65 K). However, due to the interaction between the cerium ions, the first excited state tends to be broadened as x increases, and the width of the first excited state for the dense limit of CeCu6 (TK=3.9 K) is estimated to be about 20 K. At low temperatures, Cm increases as x is decreased. This tendency is qualitatively interpreted as due to the decrease in TK caused by the increase of unit cell volume. © 1987, THE PHYSICAL SOCIETY OF JAPAN. All rights reserved.
20.
Y Maeno, T Nojima, Y Aoki, M Kato, K Hoshino, A Minami, T Fujita
Superconductivity in YBa2Cu3-yNiyO7-δ Journal Article
In: Japanese Journal of Applied Physics, vol. 26, no. 5A, pp. L774-L776, 1987.
@article{Maeno1987L774,
title = {Superconductivity in YBa2Cu3-yNiyO7-δ},
author = {Y Maeno and T Nojima and Y Aoki and M Kato and K Hoshino and A Minami and T Fujita},
doi = {10.1143/JJAP.26.L774},
year = {1987},
date = {1987-01-01},
journal = {Japanese Journal of Applied Physics},
volume = {26},
number = {5A},
pages = {L774-L776},
abstract = {Superconductivity in alloyed compounds YBa2Cu3-yNiyO7-δ has been studied in order to gain direct insights on the roles different Cu sites play in electrical conduction. Electron probe microanalysis as well as X-ray powder diffraction analysis shows that Ni is actually substituted for Cu in the oxygen-deficient perovskite compound for y at least as much as 0.27. Electrical resistivity measurements revealed that the substituted Ni does not substantially destroy the superconductivity. © 1987 IOP Publishing Ltd.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Superconductivity in alloyed compounds YBa2Cu3-yNiyO7-δ has been studied in order to gain direct insights on the roles different Cu sites play in electrical conduction. Electron probe microanalysis as well as X-ray powder diffraction analysis shows that Ni is actually substituted for Cu in the oxygen-deficient perovskite compound for y at least as much as 0.27. Electrical resistivity measurements revealed that the substituted Ni does not substantially destroy the superconductivity. © 1987 IOP Publishing Ltd.
19.
Y Maeno, T Tomita, M Kyogoku, S Awaji, Y Aoki, K Hoshino, A Minami, T Fujita
Substitution for copper in a high-Tc superconductor YBa 2Cu3O7-δ Journal Article
In: Nature, vol. 328, no. 6130, pp. 512-514, 1987.
@article{Maeno1987512,
title = {Substitution for copper in a high-Tc superconductor YBa 2Cu3O7-δ},
author = {Y Maeno and T Tomita and M Kyogoku and S Awaji and Y Aoki and K Hoshino and A Minami and T Fujita},
doi = {10.1038/328512a0},
year = {1987},
date = {1987-01-01},
journal = {Nature},
volume = {328},
number = {6130},
pages = {512-514},
abstract = {In spite of an overwhelming amount of research work1 triggered by the discovery2 of superconductivity above 90 K in an Y-Ba-Cu oxide, fundamental questions regarding the origin and mechanism of the high-Tc superconductivity in YBa2Cu3O 7-δ remain to be answered. Specifically, it has not been decided which of the two Cu sites mainly carries superconducting electrons. As an approach to the problem, we investigated superconductivity in a series of alloyed compounds, YBa2 (Cu1-xMx) 3O7-δ with M = Fe, Co, Ni, Zn and Ga, in which metals M are partially substituted for Cu. The electrical resistivity measurements, as well as the X-ray analysis at low temperatures, show that Tc is not sensitive to the orthorhombic-tetragonal phase transition induced by the impurities, thus strongly suggesting that superconductivity along the one-dimensional Cu-O chains is unlikely. © 1987 Nature Publishing Group.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
In spite of an overwhelming amount of research work1 triggered by the discovery2 of superconductivity above 90 K in an Y-Ba-Cu oxide, fundamental questions regarding the origin and mechanism of the high-Tc superconductivity in YBa2Cu3O 7-δ remain to be answered. Specifically, it has not been decided which of the two Cu sites mainly carries superconducting electrons. As an approach to the problem, we investigated superconductivity in a series of alloyed compounds, YBa2 (Cu1-xMx) 3O7-δ with M = Fe, Co, Ni, Zn and Ga, in which metals M are partially substituted for Cu. The electrical resistivity measurements, as well as the X-ray analysis at low temperatures, show that Tc is not sensitive to the orthorhombic-tetragonal phase transition induced by the impurities, thus strongly suggesting that superconductivity along the one-dimensional Cu-O chains is unlikely. © 1987 Nature Publishing Group.
18.
H Fujii, Y Uwatoko, M Akayama, K Satoh, Y Maeno, T Fujita, T Fujita, J Sakurai, H Kamimura
Magnetic and transport properties of new kondo compounds cetin (t=ni, pd and pt) Journal Article
In: Japanese Journal of Applied Physics, vol. 26, no. S3-1, pp. 549-550, 1987.
@article{Fujii1987549,
title = {Magnetic and transport properties of new kondo compounds cetin (t=ni, pd and pt)},
author = {H Fujii and Y Uwatoko and M Akayama and K Satoh and Y Maeno and T Fujita and T Fujita and J Sakurai and H Kamimura},
doi = {10.7567/JJAPS.26S3.549},
year = {1987},
date = {1987-01-01},
journal = {Japanese Journal of Applied Physics},
volume = {26},
number = {S3-1},
pages = {549-550},
abstract = {Measurements of magnetic susceptibility, electrical resistivity and thermoelectric power have been made on the CeTIn system (T=Ni, Pd and Pt) with the hexagonal Fe2P-type structure. The results suggest that CeNiIn is an intermediate valence compound with Kondo-like anomalies in resistivity ρm(T), and CePdIn is a heavy fermion compound with doubie-peak structures in both ρm(T) and S(T) and exhibits an antiferromagnetic order at TN=1.8 K, whereas CePtIn is a heavy fermion peak in ρm(T) and shows no magnetic and superconducting transitions. © 1987 The Japan Society of Applied Physics.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Measurements of magnetic susceptibility, electrical resistivity and thermoelectric power have been made on the CeTIn system (T=Ni, Pd and Pt) with the hexagonal Fe2P-type structure. The results suggest that CeNiIn is an intermediate valence compound with Kondo-like anomalies in resistivity ρm(T), and CePdIn is a heavy fermion compound with doubie-peak structures in both ρm(T) and S(T) and exhibits an antiferromagnetic order at TN=1.8 K, whereas CePtIn is a heavy fermion peak in ρm(T) and shows no magnetic and superconducting transitions. © 1987 The Japan Society of Applied Physics.
17.
T Fujita, Y Aoki, Y Maeno, J Sakurai, H Fukuba, H Fujii, T Okamoto, K Kumagai, M Kurisu, H Kadomatsu, H Fujiwara
High-Tc Superconductivity and Phase Diagram of (La1-xBax)2CuO4-y Journal Article
In: Japanese Journal of Applied Physics, vol. 26, no. S3-2, pp. 1041-1042, 1987.
@article{Fujita19871041,
title = {High-Tc Superconductivity and Phase Diagram of (La1-xBax)2CuO4-y},
author = {T Fujita and Y Aoki and Y Maeno and J Sakurai and H Fukuba and H Fujii and T Okamoto and K Kumagai and M Kurisu and H Kadomatsu and H Fujiwara},
doi = {10.7567/JJAPS.26S3.1041},
year = {1987},
date = {1987-01-01},
journal = {Japanese Journal of Applied Physics},
volume = {26},
number = {S3-2},
pages = {1041-1042},
abstract = {The lattice, magnetic and superconducting properties of the oxides, (La1-xMx)2CuO4-y (M=Ba, Ca), were extensively investigated as a function of both temperature T and Ba-concentration x. For x > 0.025 the compounds show a superconducting transition, with which two different types of phase transitions were found to compete in the T-x plane; crystal distortion from a tetragonal to an orthorhombic lattice and antiferromagnetic ordering. External hydrostatic pressure tends to depress the magnetic ordering and to enhance superconductivity. © 1987 The Japan Society of Applied Physics.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
The lattice, magnetic and superconducting properties of the oxides, (La1-xMx)2CuO4-y (M=Ba, Ca), were extensively investigated as a function of both temperature T and Ba-concentration x. For x > 0.025 the compounds show a superconducting transition, with which two different types of phase transitions were found to compete in the T-x plane; crystal distortion from a tetragonal to an orthorhombic lattice and antiferromagnetic ordering. External hydrostatic pressure tends to depress the magnetic ordering and to enhance superconductivity. © 1987 The Japan Society of Applied Physics.
16.
Y Kitano, K Kifune, I Mukouda, H Kamimura, J Sakurai, Y Komura, K Hoshino, M Suzuki, A Minami, Y Maeno, M Kato, T Fujita
Analysis of crystal structure of an Y-Ba-Cu oxide Journal Article
In: Japanese Journal of Applied Physics, vol. 26, no. 4 A, pp. L394-L396, 1987.
@article{Kitano1987L394,
title = {Analysis of crystal structure of an Y-Ba-Cu oxide},
author = {Y Kitano and K Kifune and I Mukouda and H Kamimura and J Sakurai and Y Komura and K Hoshino and M Suzuki and A Minami and Y Maeno and M Kato and T Fujita},
doi = {10.1143/JJAP.26.L394},
year = {1987},
date = {1987-01-01},
journal = {Japanese Journal of Applied Physics},
volume = {26},
number = {4 A},
pages = {L394-L396},
abstract = {Results of the analyses on crystal structure and chemical composition of dark-green crystals mainly found in an Y-Ba-Cu oxide specimen which shows highc superconductivity are reported. Crystal structure is investigated by the electron diffraction method and is determined to be orthorhombic with lattice parameters =1.22 nm, =0.561 nm and =0.714nm, and with a space group Pnma (No. 62) or Pna21 (No. 33). Expected -values are presented and are successfully compared with the X-ray powder diffraction spectrum obtained from this oxide. Chemical composition is analyzed by the EPMA method and is determined to be Y2BaCuO5 for the oxide. © 1987 IOP Publishing Ltd.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Results of the analyses on crystal structure and chemical composition of dark-green crystals mainly found in an Y-Ba-Cu oxide specimen which shows highc superconductivity are reported. Crystal structure is investigated by the electron diffraction method and is determined to be orthorhombic with lattice parameters =1.22 nm, =0.561 nm and =0.714nm, and with a space group Pnma (No. 62) or Pna21 (No. 33). Expected -values are presented and are successfully compared with the X-ray powder diffraction spectrum obtained from this oxide. Chemical composition is analyzed by the EPMA method and is determined to be Y2BaCuO5 for the oxide. © 1987 IOP Publishing Ltd.
1986
15.
R E Ecke, H Haucke, Y Maeno, J C Wheatley
Critical dynamics at a Hopf bifurcation to oscillatory Rayleigh- Bénard convection Journal Article
In: Physical Review A, vol. 33, no. 3, pp. 1870-1878, 1986.
@article{Ecke19861870,
title = {Critical dynamics at a Hopf bifurcation to oscillatory Rayleigh- Bénard convection},
author = {R E Ecke and H Haucke and Y Maeno and J C Wheatley},
doi = {10.1103/PhysRevA.33.1870},
year = {1986},
date = {1986-01-01},
journal = {Physical Review A},
volume = {33},
number = {3},
pages = {1870-1878},
abstract = {The steady-state and dynamic properties of the transition to oscillatory convection in a low-Prandtl-number fluid, dilute He3 in superfluid He4, are presented. Critical slowing down is observed and characterized by a phenomenological Landau-Hopf equation in analogy with equilibrium mean-field critical phenomena. In contrast to the onset of classical time-independent Rayleigh-Bénard convection, where appreciable rounding is typically observed, there is no measurable rounding at the oscillatory onset down to a reduced Rayleigh number of 3×10-4. Possible reasons for this are discussed. Different functional singularities are observed for the rms amplitudes of the fundamental and first harmonic spectral components of the oscillation. Finally, the Prandtl-number dependence of the parameters of the dynamics is presented. © 1986 The American Physical Society.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
The steady-state and dynamic properties of the transition to oscillatory convection in a low-Prandtl-number fluid, dilute He3 in superfluid He4, are presented. Critical slowing down is observed and characterized by a phenomenological Landau-Hopf equation in analogy with equilibrium mean-field critical phenomena. In contrast to the onset of classical time-independent Rayleigh-Bénard convection, where appreciable rounding is typically observed, there is no measurable rounding at the oscillatory onset down to a reduced Rayleigh number of 3×10-4. Possible reasons for this are discussed. Different functional singularities are observed for the rms amplitudes of the fundamental and first harmonic spectral components of the oscillation. Finally, the Prandtl-number dependence of the parameters of the dynamics is presented. © 1986 The American Physical Society.
1985
14.
Y Maeno, H Haucke, R E Ecke, J C Wheatley
Oscillatory convection in a dilute3He-superfluid4He solution Journal Article
In: Journal of Low Temperature Physics, vol. 59, no. 3-4, pp. 305-345, 1985.
@article{Maeno1985305,
title = {Oscillatory convection in a dilute3He-superfluid4He solution},
author = {Y Maeno and H Haucke and R E Ecke and J C Wheatley},
doi = {10.1007/BF00683781},
year = {1985},
date = {1985-01-01},
journal = {Journal of Low Temperature Physics},
volume = {59},
number = {3-4},
pages = {305-345},
abstract = {Convective instabilities in a rectangular, unity-aspect-ratio Rayleigh-Bénard cell with a solution of 1.46%3He in superfluid4He have been studied in the temperature range 0.70-1.05 K, with a corresponding Prandtl number range of 0.045<σ<0.15. The onset of stationary convection is much like that in a classical, one-component fluid. The oscillatory instability is studied by using an extremely sensitive local temperature probe. It is found that the total heat transport efficiency is suppressed by the oscillations in the entire range of Prandtl number we have studied. The local temperature probe indicates a striking difference in the oscillatory amplitude when the sense of rotation of the convective rolls is reversed. The magnitude of the convective velocity is deduced from both the initial slope of the Nusselt number near the onset of the stationary convection and the frequency of the oscillations. Determinations of the temperature dependence of the convective velocity using these two methods agree very well. The observed behavior of the oscillatory frequency and onset condition supports the theory of oscillatory convection for a classical, low-Prandtl-number, one-component fluid. © 1985 Plenum Publishing Corporation.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Convective instabilities in a rectangular, unity-aspect-ratio Rayleigh-Bénard cell with a solution of 1.46%3He in superfluid4He have been studied in the temperature range 0.70-1.05 K, with a corresponding Prandtl number range of 0.045<σ<0.15. The onset of stationary convection is much like that in a classical, one-component fluid. The oscillatory instability is studied by using an extremely sensitive local temperature probe. It is found that the total heat transport efficiency is suppressed by the oscillations in the entire range of Prandtl number we have studied. The local temperature probe indicates a striking difference in the oscillatory amplitude when the sense of rotation of the convective rolls is reversed. The magnitude of the convective velocity is deduced from both the initial slope of the Nusselt number near the onset of the stationary convection and the frequency of the oscillations. Determinations of the temperature dependence of the convective velocity using these two methods agree very well. The observed behavior of the oscillatory frequency and onset condition supports the theory of oscillatory convection for a classical, low-Prandtl-number, one-component fluid. © 1985 Plenum Publishing Corporation.
13.
Y Maeno, H Haucke, J C Wheatley
Transition to oscillatory convection in a He3 superfluid-He4 mixture Journal Article
In: Physical Review Letters, vol. 54, no. 4, pp. 340-342, 1985.
@article{Maeno1985340,
title = {Transition to oscillatory convection in a He3 superfluid-He4 mixture},
author = {Y Maeno and H Haucke and J C Wheatley},
doi = {10.1103/PhysRevLett.54.340},
year = {1985},
date = {1985-01-01},
journal = {Physical Review Letters},
volume = {54},
number = {4},
pages = {340-342},
abstract = {The oscillatory instability of Rayleigh-Bénard convection is studied in a solution of 1.46% He3 in superfluid He4 for the Prandtl-number range 0.045<<~0.15. The observed behaviors of the oscillatory frequency and the onset condition support the theory of oscillatory convection for a classical, low-Prandtl-number, one-component fluid. © 1985 The American Physical Society.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
The oscillatory instability of Rayleigh-Bénard convection is studied in a solution of 1.46% He3 in superfluid He4 for the Prandtl-number range 0.045<<~0.15. The observed behaviors of the oscillatory frequency and the onset condition support the theory of oscillatory convection for a classical, low-Prandtl-number, one-component fluid. © 1985 The American Physical Society.
12.
K Satoh, T Fujita, Y Maeno, Y Onuki, T Komatsubara, T Ohtsuka
Anisotropic specific heat of CeCu6 in magnetic fields Journal Article
In: Solid State Communications, vol. 56, no. 4, pp. 327-331, 1985.
@article{Satoh1985327,
title = {Anisotropic specific heat of CeCu6 in magnetic fields},
author = {K Satoh and T Fujita and Y Maeno and Y Onuki and T Komatsubara and T Ohtsuka},
doi = {10.1016/0038-1098(85)90395-3},
year = {1985},
date = {1985-01-01},
journal = {Solid State Communications},
volume = {56},
number = {4},
pages = {327-331},
abstract = {The specific heat of a single crystalline CeCu6 was measured at low temperatures down to 0.15 K in magnetic fields up to 6 T. The ratio of the specific heat to temperature, C/T, showed anomalously large values at low temperatures, indicating the heavy Fermi-liquid nature of a Kondo-lattice ground state. The magnetic fields suppressed C/T at low temperatures. Varying the field directions with respect to the crystallographic axes, an anisotropy in C/T was found for the first time, which is consistent with the results of the magnetic susceptibility and the magnetoresistance at low temperatures. The observed behavior of C/T is interpreted by a simple model with Lorentzian density of states at the Fermi level. © 1985.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
The specific heat of a single crystalline CeCu6 was measured at low temperatures down to 0.15 K in magnetic fields up to 6 T. The ratio of the specific heat to temperature, C/T, showed anomalously large values at low temperatures, indicating the heavy Fermi-liquid nature of a Kondo-lattice ground state. The magnetic fields suppressed C/T at low temperatures. Varying the field directions with respect to the crystallographic axes, an anisotropy in C/T was found for the first time, which is consistent with the results of the magnetic susceptibility and the magnetoresistance at low temperatures. The observed behavior of C/T is interpreted by a simple model with Lorentzian density of states at the Fermi level. © 1985.
11.
Y Onuki, Y Shimizu, T Komatsubara, A Sumiyama, Y Oda, H Nagano, T Fujita, Y Maeno, K Satoh, T Ohtsuka
Characteristics of a new Kondo lattice substance: CeCu6 Journal Article
In: Journal of Magnetism and Magnetic Materials, vol. 52, no. 1-4, pp. 344-346, 1985.
@article{Onuki1985344,
title = {Characteristics of a new Kondo lattice substance: CeCu6},
author = {Y Onuki and Y Shimizu and T Komatsubara and A Sumiyama and Y Oda and H Nagano and T Fujita and Y Maeno and K Satoh and T Ohtsuka},
doi = {10.1016/0304-8853(85)90298-7},
year = {1985},
date = {1985-01-01},
journal = {Journal of Magnetism and Magnetic Materials},
volume = {52},
number = {1-4},
pages = {344-346},
abstract = {The anisotropic magnetic properties of CeCu6 have been experimentally obtained, and the Kondo lattice has been found to be formed above x = 0.8-0.9 in CexLa1-xCu6. © 1985.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
The anisotropic magnetic properties of CeCu6 have been experimentally obtained, and the Kondo lattice has been found to be formed above x = 0.8-0.9 in CexLa1-xCu6. © 1985.
1984
10.
H Haucke, Y Maeno, J C Wheatley
PERIOD-DOUBLING TWO-TORUS STATE IN A CONVECTING **3He-SUPERFLUID **4He SOLUTION. Conference
no. pt 2, 1984.
@conference{Haucke19841123,
title = {PERIOD-DOUBLING TWO-TORUS STATE IN A CONVECTING **3He-SUPERFLUID **4He SOLUTION.},
author = {H Haucke and Y Maeno and J C Wheatley},
year = {1984},
date = {1984-01-01},
number = {pt 2},
pages = {1123-1124},
abstract = {We present observations of the nonlinear dynamical behavior of a convecting dilute solution of **3He in superfluid **4He which approaches a chaotic state via a period-doubling sequence of one of two incommensurate frequencies.},
keywords = {},
pubstate = {published},
tppubtype = {conference}
}
We present observations of the nonlinear dynamical behavior of a convecting dilute solution of **3He in superfluid **4He which approaches a chaotic state via a period-doubling sequence of one of two incommensurate frequencies.
9.
Y Maeno, H Haucke, R Ecke, J C Wheatley
ONSET OF OSCILLATIONS IN SYMMETRIC CONVECTIVE STATES IN A SUPERFLUID **3He-**4He MIXTURE. Conference
no. pt 2, 1984.
@conference{Maeno19841125,
title = {ONSET OF OSCILLATIONS IN SYMMETRIC CONVECTIVE STATES IN A SUPERFLUID **3He-**4He MIXTURE.},
author = {Y Maeno and H Haucke and R Ecke and J C Wheatley},
year = {1984},
date = {1984-01-01},
number = {pt 2},
pages = {1125-1126},
abstract = {The oscillatory convective instability in a solution of 1. 46% **3He in superfluid **4He is studied in the Prandtl number range of 0. 04 APP 1STH sigma APP 1STH 0. 15. The observed behavior supports the theory of oscillatory convection for a classical, low-Prandtl-number, one-component fluid. A local temperature probe indicates a striking difference in the oscillatory amplitude when the sense of rotation of the convective rolls is reversed.},
keywords = {},
pubstate = {published},
tppubtype = {conference}
}
The oscillatory convective instability in a solution of 1. 46% **3He in superfluid **4He is studied in the Prandtl number range of 0. 04 APP 1STH sigma APP 1STH 0. 15. The observed behavior supports the theory of oscillatory convection for a classical, low-Prandtl-number, one-component fluid. A local temperature probe indicates a striking difference in the oscillatory amplitude when the sense of rotation of the convective rolls is reversed.
8.
H Haucke, R E Ecke, Y Maeno, J C Wheatley
Noise-induced intermittency in a convecting dilute solution of He3 in superfluid He4 Journal Article
In: Physical Review Letters, vol. 53, no. 22, pp. 2090-2093, 1984.
@article{Haucke19842090,
title = {Noise-induced intermittency in a convecting dilute solution of He3 in superfluid He4},
author = {H Haucke and R E Ecke and Y Maeno and J C Wheatley},
doi = {10.1103/PhysRevLett.53.2090},
year = {1984},
date = {1984-01-01},
journal = {Physical Review Letters},
volume = {53},
number = {22},
pages = {2090-2093},
abstract = {Measurements on a convecting dilute He3-superfluid-He4 solution show a transition from periodic to chaotic behavior via intermittency. In a region near but below the onset of intermittency, injection of external noise greater than some threshold value induces chaos. © 1984 The American Physical Society.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Measurements on a convecting dilute He3-superfluid-He4 solution show a transition from periodic to chaotic behavior via intermittency. In a region near but below the onset of intermittency, injection of external noise greater than some threshold value induces chaos. © 1984 The American Physical Society.
7.
R E Ecke, Y Maeno, H Haucke, J C Wheatley
Critical dynamics near the oscillatory instability in Rayleigh- Bénard convection Journal Article
In: Physical Review Letters, vol. 53, no. 16, pp. 1567-1570, 1984.
@article{Ecke19841567,
title = {Critical dynamics near the oscillatory instability in Rayleigh- Bénard convection},
author = {R E Ecke and Y Maeno and H Haucke and J C Wheatley},
doi = {10.1103/PhysRevLett.53.1567},
year = {1984},
date = {1984-01-01},
journal = {Physical Review Letters},
volume = {53},
number = {16},
pages = {1567-1570},
abstract = {The oscillatory temperature amplitude of a low-Prandtl-number fluid in Rayleigh-Bénard convection is shown to exhibit critical slowing down near the onset of oscillatory convection. The data are analyzed in the context of a mean-field Landau-Hopf equation. We find the magnitude of the power-law exponent for the dynamic relaxation to be 1.01±0.02 and 1.00±0.02 above and below onset, respectively, in agreement with the theoretical predictions. © 1984 The American Physical Society.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
The oscillatory temperature amplitude of a low-Prandtl-number fluid in Rayleigh-Bénard convection is shown to exhibit critical slowing down near the onset of oscillatory convection. The data are analyzed in the context of a mean-field Landau-Hopf equation. We find the magnitude of the power-law exponent for the dynamic relaxation to be 1.01±0.02 and 1.00±0.02 above and below onset, respectively, in agreement with the theoretical predictions. © 1984 The American Physical Society.
1983
6.
Yoshiteru Maeno, Hans Haucke, John Wheatley
UNDERSTANDING EXPERIMENTALLY THE TRANSITION TO CHAOS IN A CONVECTING DILUTE SOLUTION OF **3He IN SUPERFLUID **4He. Conference
no. 103, 1983.
@conference{Maeno1983412,
title = {UNDERSTANDING EXPERIMENTALLY THE TRANSITION TO CHAOS IN A CONVECTING DILUTE SOLUTION OF **3He IN SUPERFLUID **4He.},
author = {Yoshiteru Maeno and Hans Haucke and John Wheatley},
year = {1983},
date = {1983-01-01},
journal = {AIP Conference Proceedings},
number = {103},
pages = {412-427},
keywords = {},
pubstate = {published},
tppubtype = {conference}
}
5.
Yoshiteru Maeno, H Haucke, John Wheatley
SIMPLE DIFFERENTIAL THERMOMETER USING A THERMOCOUPLE WITH A SQUID DETECTOR. Conference
no. 103, 1983.
@conference{Maeno1983467,
title = {SIMPLE DIFFERENTIAL THERMOMETER USING A THERMOCOUPLE WITH A SQUID DETECTOR.},
author = {Yoshiteru Maeno and H Haucke and John Wheatley},
year = {1983},
date = {1983-01-01},
journal = {AIP Conference Proceedings},
number = {103},
pages = {467},
keywords = {},
pubstate = {published},
tppubtype = {conference}
}
4.
Y Maeno, H Haucke, J Wheatley
Simple differential thermometer for low temperatures using a thermocouple with a SQUID detector Journal Article
In: Review of Scientific Instruments, vol. 54, no. 8, pp. 946-948, 1983.
@article{Maeno1983946,
title = {Simple differential thermometer for low temperatures using a thermocouple with a SQUID detector},
author = {Y Maeno and H Haucke and J Wheatley},
doi = {10.1063/1.1137507},
year = {1983},
date = {1983-01-01},
journal = {Review of Scientific Instruments},
volume = {54},
number = {8},
pages = {946-948},
abstract = {Details of design and construction of a simple and rugged thermocouple differential thermometer are presented. Gold + 0.03 at % iron wire is used, with niobium leads connected to a SQUID. It is demonstrated that at 1 K the response time is about 15 ms and that the temperature sensitivity of 10- 7 K with a 10-Hz filter is Johnson-noise limited. Additional qualities such as small size, little self-heating, and high reproducibility make this device ideal for differential thermometry at low temperatures.},
keywords = {},
pubstate = {published},
tppubtype = {article}
}
Details of design and construction of a simple and rugged thermocouple differential thermometer are presented. Gold + 0.03 at % iron wire is used, with niobium leads connected to a SQUID. It is demonstrated that at 1 K the response time is about 15 ms and that the temperature sensitivity of 10- 7 K with a 10-Hz filter is Johnson-noise limited. Additional qualities such as small size, little self-heating, and high reproducibility make this device ideal for differential thermometry at low temperatures.
