Abstract
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 0.06 K. The temperature dependence of the magnetization M(T) at 0.1 kOe exhibits two distinct anomalies at Tc1 = 1.83 K and Tc2 = 1.65 K, 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 10 kOe, 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 40 kOe, 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 ΓI singlet as the possible ground state of Pr3+ in PrOs4 Sb12.
Original language | English |
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Pages (from-to) | 1516-1522 |
Number of pages | 7 |
Journal | Journal of the Physical Society of Japan |
Volume | 72 |
Issue number | 6 |
DOIs | |
State | Published - 2003/06 |
Keywords
- Crystalline electric field effect
- Heavy-fermion superconductor
- Magnetization
- Mixed state
- Phase diagram
- PrOsSb
ASJC Scopus subject areas
- General Physics and Astronomy