This is were we announce new journal articles and conference proceedings published by members of the group.
Frustrated systems, in which spin arrangement is not uniquely determined, have attracted attention because peculiar phenomena can occur. Recently, we found the T-linear behavior of the nuclear spin-lattice relaxation rate 1/T1 in the frustrated semiconductor YbCuS2 with a Yb zigzag chain. This behavior indicates the presence of charge-neutral quasiparticles. To investigate the origin and characteristics […]
We report the re-measurement of the a-axis spin susceptibility component in an early-stage sample of the spin-triplet superconductor UTe2 with the transition temperature of TSC = 1.6 K. Using Knight-shift measurements along the b axis and at a 10-degree tilt from the b axis towards the a axis, we accurately determined the a-axis component without directly measuring the a-axis Knight shift. Our results reveal a decrease of […]
Nanoparticles were predicted to exhibit unique physical properties due to quantum size effects, but their identification remains difficult.According to Kubo’s theory, the gap size is inversely correlated with both the density of states at the Fermi energy and the number of atoms in the particle.Previously, we confirmed that the particle size and magnetic field dependence […]
Superconducting (SC) state has spin and orbital degrees of freedom, and spin-triplet superconductivity shows multiple SC phases because of the presence of these degrees of freedom. However, the observation of spin-direction rotation occurring inside the SC state (SC spin rotation) has hardly been reported. Uranium ditelluride, a recently found topological superconductor, exhibits various SC phases […]
The emergence of charge-neutral fermionic excitations in magnetic systems is one of the unresolved issues in recent condensed matter physics. This type of excitations has been observed in various systems, such as low-dimensional quantum spin liquids, Kondo insulators, and antiferromagnetic insulators. Here, we report the presence of a pronounced gapless spin excitation in the low-temperature […]
Recently, a superconducting (SC) transition from low-field (LF) to high-field (HF) SC states was reported in CeRh2As2, indicating the existence of multiple SC states. It has been theoretically noted that the existence of two Ce sites in the unit cell, the so-called sub-lattice degrees of freedom owing to the local inversion symmetry breaking at the […]
Translational symmetry breaking in fluid is antagonistic but can be realized insuperconductivity, which is quantum-mechanical coherent fluid formed byelectron pairs. This novel superconducting state, known as the Fulde-Ferrell-Larkin-Ovchinnikov (FFLO) state, can be induced by time-reversal-symmetrybreaking magnetic field applied to spin-singlet superconductors. This stateintrinsically causes the superconducting spin smecticity, spin-density-modulatedfluidity with spontaneous translational-symmetry breaking. Detection of […]
To investigate the normal-state magnetic properties of UTe 2 under pressure, weperform 125 Te nuclear magnetic resonance (NMR) measurements up to 2 GPa.Below 1.2 GPa, the b -axis NMR Knight shift shows a broad maximum at the so-called T χ max on cooling, which is consistent with the magnetizationmeasurement under pressure. T χ max decreases […]
In the Mott insulator Ca2RuO4, which is a strongly correlated material material, we observed for the first time the generation of high-order harmonics that convert a strong infrared laser beam into visible light. Our experiments show that the intensity of the generated signal follows a surprisingly simple rule. In recent years, with the development of ultrashort […]
Spatial inversion symmetry in crystal structures is closely related to the superconducting (SC) and magnetic properties of materials. Recently, several theoretical proposals that predict various interesting phenomena caused by the breaking of the local inversion symmetry have been presented. However, experimental validation has not yet progressed owing to the lack of model materials. Here we […]