Yoshiki Nakanishi

Possible Octupole Ordering in Phase II of SmRu4P12 Suggested from Elastic Constants

We have studied the origin of the successive phase transitions in filled skutterudite SmRu 4 P 12 based on the results of elastic constant measurements. The temperature dependence of the elastic co...

Structural Quantum Criticality and Superconductivity in Iron-Based Superconductor Ba(Fe1-xCox)2As2

We investigated the elastic properties of the iron-based superconductor Ba(Fe 1- x Co x ) 2 As 2 with eight Co concentrations. The elastic constant C 66 shows a large elastic softening associated with structural phase transition. C 66 was analyzed on the basis of the localized and itinerant pictures of Fe-3d electrons, which shows a strong electron–lattice coupling and a possible mass enhancement in this system. The results are similar to those of unconventional superconductors, where the properties of the system are governed by quantum fluctuations associated with the zero-temperature critical point of long-range order, namely, the quantum critical point (QCP). In this system, the inverse of C 66 behaves just like the magnetic susceptibility in magnetic QCP systems. Although the QCPs of these existing superconductors are all ascribed to antiferromagnetism, our systematic studies on the canonical iron-based superconductor Ba(Fe 1- x Co x ) 2 As 2 have revealed that there is a signature of “structural quan...

Elastic Anomalies of Polycrystalline SmRu4P12 Associated with Metal–Insulator Transition

The longitudinal and transverse elastic constants of polycrystalline SmRu 4 P 12 have been measured as a function of temperature in the magnetic field up to 12 T. The transverse elastic constant shows a weak softening toward low temperatures. Both longitudinal and transverse elastic constants show a large anomaly below the metal–insulator transition T MI = 16 K. These elastic anomalies indicate the ground state of the crystalline electric field multiplet to be Γ 8 , and that the quadrupole ordering is responsible for this metal insulator transition. The successive anomalies of SmRu 4 P 12 have been clearly observed by ultrasonic measurements. An elastic anomaly was found at T * , which is 14 K in the absence of a magnetic field. T MI increases and T * decreases under the application of the magnetic field. The anomaly at T * is markedly enhanced by the application of a magnetic field.

Elastic properties of the non-Fermi-liquid metal CeRu4Sb12 and dense Kondo semiconductor CeOs4Sb12

We have investigated the elastic properties of the Ce-based filled skutterudite antimonides CeRu

Elastic properties of Re-Ru4Sb12 (Re; La, Pr)

_{4}

Strange Inter-Layer Properties of Ba(Fe1-xCox)2As2 Appearing in Ultrasonic Measurements

Sb

Possible High TQ in YbAl3C3 with 4 f13 System

_{12}

Anomalous elastic softening of Sm Ru 4 P 12 under high pressure

and CeOs

Elastic and Magnetic Properties of Bilayer Manganites: La2-2xSr1+2xMn2O7 for x=0.35 and 0.40

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Absence of Jahn−Teller transition in the hexagonal Ba3CuSb2O9 single crystal

Sb