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The linear thermal expansion of polycrystalline CeRhSb has been measured in the temperature range 77 K < T < 300 K under hydrostatic pressure up to 2.3 GPa. It is found that the thermal expansion coefficient α(T) at ambient pressure shows a maximum around Tmax = 140 K and Tmax increases with increasing pressure having rate of ∂Tmax/∂P = + 38.5 K/GPa. This fact shows that the Kondo temperature TK is increased by applying pressure.

The effect of hydrostatic pressure on the viability of soil microorganisms has been examined to develop a new method of sterilization without using agricultural chemicals and to explore the habitable zone of the microorganisms in the earth's interior. It is found that almost all microorganisms in soil cannot survive above 0.75 GPa at room temperature but a small amount of microorganisms are still alive above 0.75 GPa. The slow rate of releasing pressure is found to have a small effect on the viability. [ABSTRACT FROM AUTHOR]

The magnetoresistances (MRs) of Cr and Cr0.985V0.015 (Cr-V) alloy have been measured at high pressures up to 2.0 GPa in order to elucidate the relation between the transport properties and spin density wave (SDW) antiferromagnetic state. The resistance of Cr is found to increase with increasing magnetic field (H). MR ratios of Cr and Cr-V alloy at room temperature are nearly 0% and 0.3% at 7 T, respectively. But at 77 K, these are 70% and 30% at 7 T at ambient pressure, respectively. MR ratio of Cr at 77 K is found to show a peak ∼1.3 GPa but that of Cr-V alloy decreases smoothly with pressure. The origins of the pressure dependence in the magnitude of MR are discussed in connection with the SDW antiferromagnetic states. [ABSTRACT FROM AUTHOR]

Abstract: The electrical resistivity and magnetoresistance (MR) of single crystalline -Ce have been measured under high pressure and low temperature. It is found that the temperature dependence of resistivity at low temperature is described as below 10 K, where is the residual resistivity and A is the constant. A decreases significantly as pressure increases, which corresponds to the increase of Kondo temperature at high pressure. A seems to be divergent from higher pressures toward 0.3 GPa, which suggests the existence of magnetic phase boundary. MR ratio of -Ce is positive and enhanced by applying pressure. These results are discussed on the basis of theoretical model presented by Kawakami–Okiji. [Copyright &y& Elsevier]

Abstract: The thermal expansion coefficients of Kondo compounds, CeBe13 and CeRh2Si2, and the magnetostriction of Tb0.3Dy0.7Fe2(Terfenol-D) have been measured at high pressure. By simple analysis using thermodynamical relation, it is found that the density of state at the Fermi level and the Grüneisen parameters of the Kondo compounds decrease rapidly with increasing pressure corresponding to the large pressure-induced enhancement of Kondo temperatures. An anomalous behaviour in the thermal expansion coefficients of CeRh2Si2 is observed at high pressure above . This anomaly is suggested as an origin of pressure-induced superconductivity. The giant magnetostriction (GMS) of Terfenol-D is found to be enhanced by applying hydrostatic pressure below 0.5 GPa but GMS decreases above it. These results are discussed briefly by comparing with the previous ones. [Copyright &y& Elsevier]

Abstract: The thermal expansion and lattice constants of perovskite have been measured at high pressure. It is found that an anomalous expansion due to metal–insulator transition appeared on heating in the temperature dependence of the thermal expansion and its magnitude decreases with increasing pressure. The metal–insulator transition temperature, , increases with increasing pressure. The lattice constants, a, b, and c are found to decrease with increasing pressure but there is a large anisotropy in the lattice compression. The linear com are extracted to be 1.5, 1.9 and for a, b and c-axis, respectively. [Copyright &y& Elsevier]

The electrical resistance and the magnetoresistance (MR) in Fe/Cr multilayers have been measured at high pressure. It is found that the effect of pressure on the MR ratio and saturation field (Hs) was significant and the spin-dependent scattering plays an important role in the pressure dependence of MR ratio. The pressure change of Hs is suggested to be dominated by the change in the value on |J| at high pressure. [Copyright &y& Elsevier]

The electrical resistivity of single crystalline HoNi[sub 2]B[sub 2]C has been measured at high pressure and magnetic fields. The three anomalies in the magnetoresistance due to metamagnetic transitions are observed both at ambient and high pressures. It is found that the metamagnetic transition fields increase with increasing pressure. The temperature dependence of electrical resistivity is strongly dependent on magnetic field. Non Fermi liquid behavior is observed near the metamagnetic transition fields. But the normal Fermi liquid behavior recovers after completing the phase transition. The Grüneisen parameters are also calculated to examine the stability of electronic state. [ABSTRACT FROM AUTHOR]

Abstract: The effects of pressure on the magnetization (M) and the magnetostriction (MS) for DyB6 single crystal have been measured at 4.2K. It is found that the M loops are insensitive to pressure, whereas the large MS with magnitude of 0.5% at 5T at ambient pressure is rapidly suppressed by applying pressure. The metamagnetic transition field H M in the M curve increases slightly by applying pressure with the rate of increase, ∂ln H M/∂P, of 0.03GPa−1, which is almost the same value as that for T N, 0.04GPa−1. [Copyright &y& Elsevier]

Abstract: The electrical resistivity of SrFeWMoO has been measured under high pressure in order to make the transport properties of this compound clear. The resistivity decreased with increasing pressure and the magnitude of pressure coefficient below 1GPa is larger than that above 1GPa. It is found that the electrical resistivity shows a temperature dependence, which implies that the conduction of electrons is mainly dominated by a variable range hopping. The coefficient of is decreased by applying pressure and is different between, below and above 1GPa. These results suggest that a kind of phase transition or crossover occurs around 1GPa. [Copyright &y& Elsevier]

Abstract: The electrical resistivity of single crystalline has been measured at high pressure up to 6GPa. It is found that the heavy fermion state becomes unstable at around 2.8GPa, where the coefficient of dependence diverges and the Kondo temperature is 0. This fact indicates the occurrence of quantum phase transition near 2.8GPa. The result will be discussed in connection with the disappearance of the antiferromagnetic ordering temperature near 3GPa. [Copyright &y& Elsevier]

Abstract: The compounds are well known to show a large magnetoresistance (MR) near the M–I phase boundary . The magnetoresistance and AC susceptibility of , which is on the border of M–I phase boundary, have been measured under high pressure. The MR decreases with increasing pressure, especially, at low field of around 2T. The Curie temperature, , is obtained by the temperature dependence of AC susceptibility. is found to increase with pressure with a rate of . [Copyright &y& Elsevier]

Abstract: The electrical resistivity of ordered has been observed at high pressure up to 15GPa. Above 4.5GPa, dependence in the temperature dependent electrical resistivity is observed. The coefficients are found to increase with pressure and show a divergence near 16GPa. This result indicates a quantum critical point near 16GPa. [Copyright &y& Elsevier]

Abstract: The electrical resistance of a single crystal of HoNi2B2C has been measured as a function of temperature (T) and magnetic field (H) under high pressure (P). As pressure increases, decreases with the rate of  K/GPa but increases with  K/GPa. This implies that the superconductivity above competes with antiferromagnetism. The re-entrant superconducting temperature coexisting with the antiferromagnetic phase is increased by applying pressure. The present result indicates that coincides with near 3.2 GPa. [Copyright &y& Elsevier]

Abstract: We investigated elastic properties of the filled skutterudite compound with heavy lanthanide TbRu4P12 by means of ultrasonic measurements under pressure for the first time. TbRu4P12 undergoes a two successive phase transition from a paramagnetic to an antiferromagnetically ordered phase at , then to another phase transition at . We found that a clear elastic anomaly was observed at the two successive phase transition. Furthermore, it is found that they both show a significant pressure dependence. A steep decrease closely associated with is suppressed significantly, but it hardly shifts by applying the pressure. On the other hand, a slight anomaly associated with is gradually suppressed and shifts to lower temperatures by applying the pressure. We argue the elastic behavior and the possible interpretation in each ordering phase. [Copyright &y& Elsevier]

Abstract: The thermal expansion and lattice constants of polycrystalline GdAl2 have been measured under high pressure. It is found that as pressure increases, the Curie temperature increases with a ratio of  K/GPa and the spontaneous volume magnetostriction decreases rapidly. C15 structure is stable up to 12.4 GPa and the bulk modulus is 75.3 GPa at room temperature. Grüneisen parameter of is estimated to be 3.84. Using these experimental results, the pressure dependence of is discussed on the basis of the itinerant electron model of ferromagnetism. [Copyright &y& Elsevier]

Abstract: We have measured the transverse elastic constant of under hydrostatic pressure of 0.35GPa in the magnetic field up to 12T. The magnetic transition temperature is enhanced by applying pressure in large, while the metal-insulator (M–I) transition temperature increases slightly. These behaviors are very consistent with the evaluation of Grüneisen parameters by using the thermodynamic relation. The order parameter for the M–I transition was discussed on the basis of this pressure experiment. [Copyright &y& Elsevier]

The electrical resistivity of single crystalline CeRh2Si2 has been measured in the temperature range from 2.0 to 300 K under high pressure up to 2.3 GPa. The coefficient of T2 term A(P) and the residual resistivity ρ0(P) have been obtained as a function of pressure. It is found that A(P) shows one maximum and ρ0(P) show two maxima near the pressure where the magnetic ordering phases disappear. The result is discussed on the basis of pressure-induced quantum phase transition. [Copyright &y& Elsevier]