23 research outputs found
La-concentration dependence of the low-temparature properties in Pr_{1-x}La_xPb_3
We have studied the low temperature properties of Pr_{1-x}La_xPb_3 with the ground state of a non-Kramers for . From the concentration dependence of the specific heat, the quadrupolar ordeing, which is observed at in PrPb_3, is expected to occur only up to . For a wide range of La concentration for where the ordering is absent, the specific heat shows a T-linear variation below 0.5 K with a large coefficient, and can be almost reproduced by the model for amorphous materials with a random configuration of two level system. This means that the large is responsible for the superpose of the Schottky specific heat due to splitting of the doublet by the distortion of CEF field. For , increases monotonically with decreasing temperature and can not be reproduced by the above model
In situ Magnetization Measurement of Superconducting Transition in PdH0.82 and PdD0.79 Prepared by Low-Temperature Absorption
We studied the superconducting properties of Pd hydride and deuteride prepared by a low temperature absorption method using in situ magnetization measurements down to T = 0.5 K. The absorption was performed under hydrogen (H2) or deuterium (D2) gas atmosphere at T = 200 K, where the gas pressure and magnetization were monitored simultaneously. From the pressure change caused by the absorption of H (D) in Pd sample, the H (D) content was determined to be 0.82 (0.79). The superconducting state was observed below T ∼ 1.3 K for the both systems. This state was investigated through precise magnetization measurements. The results suggest that H or D atoms are absorbed uniformly over the whole sample.</p
Volume shrinkage dependence of ferromagnetic moment in lanthanide ferromagnets gadolinium, terbium, dysprosium, and holmium
The Gd–Ho series of lanthanide ferromagnets, which includes gadolinium (Gd), terbium (Tb), dysprosium (Dy), and holmium (Ho), undergoes similar structural transitions, e.g., the hcp→Sm-type→dhcp→fcc transitions, under pressure. Through high-field DC magnetic measurements and structural analyses, we found that the ferromagnetic moments disappeared at a specified critical pressure, which resulted in volume shrinkage of 16.7±1.7% for each ferromagnet. The results of the present study suggest that the disappearance of the ferromagnetic moments of Gd–Ho under pressure could be understood within the framework of a band picture related to volume shrinkage