Yoshiteru MAENO

Professor, Department of Physics, Kyoto University

Field of Specialty：: Low temperature physics (Experiment)
Topics of Research：: (A01) Novel Edge Phenomena in Superconductors with Broken Time-Reversal Symmetry
Specific Topics：: Study of topological superconducting phenomena using Sr₂RuO₄ superconductor

■ Laboratory Website

RESEARCH

The main research interest of my group is the physics of ruthenates. These are ruthenium oxide materials with the same crystal structure group as the cuprate superconductors (i.e. the well-known copper-oxide high-T_c superconductors). In 1994, we discovered superconductivity in the ruthenate Sr₂RuO₄, and since then we have developed an extensive world-wide collaboration of research on these materials.
Ruthenate superconductivity is now believed to result from a revolutionary "spin-triplet" pairing, in which not only the electronic charges but also the active spins of electrons exhibit superfluid properties. We grow high-quality single crystals and investigate their unconventional superconductivity with various low-temperature techniques including calorimetry (specific heat), uni-axial pressure, and junctions.
Our other interests include oxide materials with geometrically frustrated spins. Using high-quality crystals we grow, we investigate their unusual physical properties, such as spin-ice and Kagome-ice states as well as the unconventional anomalous Hall effect (UAHE). The ultimate aims of investigating these materials for us are to search for superconductivity based on unconventional features. With the common purpose, we also study various non-centrosymmetric superconductors.

In this project "Topological Quantum Phenomena in Condensed Matter with Broken Symmetries", we pursue novel superconducting phenomena in pure and eutectic ruthenate systems to reveal their topological aspects, as well as to obtain truly conclusive evidence for their pairing symmetry. As the project leader, I will actively promote the interdisciplinary collaborations throughout our project based on my experience in studying superconductors, superfluids, and exotic insulators.

EDUCATION

1979: B.Sc. in Physics, Kyoto University (Advisors: Akira Hirai and Takao Mizusaki)
1980: M.S. in Physics, University of California, San Diego
1984: Ph.D. in Physics, University of California, San Diego (Advisor: John Wheatley)

PROFESSIONAL EXPERIENCE

1984-1988: Research Associate, Associate Professor, Department of Physics,
Hiroshima University
1988-1989: Visiting Scientist, IBM Research, Rüschlikon (Zurich), Switzerland (Host: Georg Bednorz)
1989-1996: Associate Professor, Department of Physics, Hiroshima University
1996-2001: Associate Professor, Department of Physics, Kyoto University
2001-2006: Professor, International Innovation Center, and Department of
Physics, Kyoto University.
2006-Present: Professor, Department of Physics, Kyoto University

HONORS AND AWARDS

2000: Superconductivity Science and Technology Award
(Co-awarded with M. Sigrist)
2000: Ryogo Kubo Memorial Award
2002: Japan IBM Science Award
2004: Thomson Scientific Research Front Award
2004: Daiwa Adrian Prizes
(Co-awarded with A.P. Mackenzie and eight others)
2008: Science and Technology Award of Minister of Education, Culture,Sports,
Science and Technology of Japan
(co-awarded with H. Nishimura and three others)
2009: Bernd T. Matthias Prize (Co-awarded with H. Hosono)

SELECTION OF PUBLICATIONS

"First-order Superconducting Transition of Sr₂RuO₄"
S. Yonezawa, T. Kajikawa, and Y. Maeno,
Phys. Rev. Lett. 110, 077003-1-5 (Feb. 2013).

"Evaluation of Spin-Triplet Superconductivity in Sr₂RuO₄"
Y. Maeno, S. Kittaka, T. Nomura, S. Yonezawa, K. Ishida,
J. Phys. Soc. Jpn. 81, 011009-1-29 (Jan. 2012).

"Topological Competition of Superconductivity in Pb/Ru/Sr₂RuO₄ Junctions"
T. Nakamura, R. Nakagawa, T. Yamagishi, T. Terashima, S. Yonezawa, M. Sigrist, Y. Maeno,
Physical Review B 84, 060512(R)-1-4 (Aug. 2011).

"Higher-T_c Superconducting Phase in Sr₂RuO₄ Induced by Uniaxial Pressure",
S. Kittaka, H. Taniguchi, S. Yonezawa, H. Yaguchi, and Y. Maeno,
Phys. Rev. B 81, 180510(R), (May 2010).

"High Resolution Polar Kerr Effect Measurements of Sr₂RuO₄: Evidence for Broken Time-Reversal Symmetry in the Superconducting State,
J. Xia, Y. Maeno, P. T. Beyersdorf, M. M. Fejer, and A. Kapitulnik,
Phys. Rev. Lett. 97, 167002-1-4 (Oct. 2006).

"Determination of the Superconducting Gap Structure in All Bands of the Spin-Triplet Superconductor Sr₂RuO₄",
K. Deguchi, Z. Q. Mao, and Y. Maeno,
J. Phys. Soc. Jpn. 73, 1313-1321 (May 2004).

"The Superconductivity of Sr₂RuO₄ and the Physics of Spin-Triplet Paring",
A.P. Mackenzie and Y. Maeno,
Reviews of Modern Physics 75, 657-712 (April 2003).

"Spin-Triplet Superconductivity in Sr₂RuO₄ Identified by ¹⁷O Knight Shift",
K. Ishida, H. Mukuda, Y. Kitaoka, A. Asayama, Z. Q. Mao, Y. Mori, and Y. Maeno,
Nature 396, 658-660 (Dec. 1998).

"Enhancement of Superconductivity of Sr₂RuO₄ to 3 K by Embedded Metallic Microdomains",
Y. Maeno, T. Ando, Y. Mori, E. Ohmichi, S. Ikeda, S. NishiZaki, and S. Nakatsuji,
Phys. Rev. Lett. 81, 3765-3768 (Oct. 1998).

"Time-Reversal Symmetry Breaking Superconductivity in Sr₂RuO₄",
G. M. Luke, Y. Fudamoto, K.M. Kojima, M.I. Larkin, J. Merrin, B. Nachumi, Y. J. Uemura,
Y. Maeno, Z. Q. Mao, Y. Mori, H. Nakamura, and M. Sigrist,
Nature 394, 558-561 (Aug. 1998).

"Superconductivity in a Layered Perovskite without Copper",
Y. Maeno, H. Hashimoto, K. Yoshida, S. Nishizaki, T. Fujita, J. G. Bednorz, and F. Lichtenberg,
Nature 372, 532-534 (Dec. 1994).

"Substitution for Copper in a High-T_c Superconductor YBa₂Cu₃O_7-δ",
Y. Maeno, T. Tomita, M. Kyogoku, S. Awaji, Y. Aoki, K. Hoshino, A. Minami, and T. Fujita,
Nature 328, 512-514 (Aug. 1987).

"Transition to Oscillatory Convection in a ³He-Superfluid- ⁴He Mixture",
Y. Maeno, H. Haucke, and J. C. Wheatley,
Phys. Rev. Lett. 54, 340-342 (Jan. 1985).