2003/03/26 by T. Tayama, T. Sakakibara, Hitoshi Sugawara +5
Materials Science · Physics and Astronomy · #Advanced Condensed Matter Physics #Iron-based superconductors research #Rare-earth and actinide compounds #cond-mat.str-el #cond-mat.supr-con
paper · pdf · doi:10.1016/j.jmmm.2003.12.710
14 pages, 11 figures, To be published in J. Phys. Soc. Jpn
arxiv created 2003/03/26 · openalex publication_date 2004/01/13 · arxiv updated 2009/11/30 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/28
We investigated the magnetic phase diagram of the first Pr-based heavy fermion superconductor PrOs4Sb12 by means of high-resolution dc magnetization measurements in low temperatures down to 0.06K. The temperature dependence of the magnetization M(T) at 0.1kOe exhibits two distinct anomalies at Tc1=1.83K and Tc2=1.65K, in agreement with the specific heat measurements at zero field. Increasing magnetic field H, both Tc1(H) and Tc2(H) move toward lower temperatures without showing a tendency of intersecting to each other. Above 10kOe, the transition at Tc2(H) appears to merge into a line of the peak effect which is observed near the upper critical field Hc2 in the isothermal M(H) curves, suggesting a common origin for these two phenomena. The presence of the field-induced ordered phase (called phase A here) is confirmed for three principal directions above 40kOe, with the anisotropic A-phase transition temperature TA: TA[100] > TA[111] >TA[110]. The present results are discussed on the basis of crystalline-electrical-field level schemes with a non-magnetic ground state, with emphasis on a Gamma1 singlet as the possible ground state of Pr3+ in PrOs4Sb12.