Thermal and magnetic properties of the low-temperature antiferromagnet Ce4Pt12Sn25

Article

关键词: FERMI-LIQUID BEHAVIOR;    KONDO-LATTICE;    DIAGRAM;    HEAT;   

DOI  :  10.1103/PhysRevB.82.174426

来源: SCIE

【 摘 要 】

We report specific heat (C) and magnetization (M) of single crystalline Ce4Pt12Sn25 at temperature down to similar to 50 mK and in fields up to 3 T. C/T exhibits a sharp anomaly at 180 mK, with a large Delta C/T similar to 30 J/mol Ce K-2, which, together with the corresponding cusplike magnetization anomaly, indicates an antiferromagnetic (AFM) ground state with a Neel temperature T-N = 180 m K. Numerical calculations based on a Heisenberg model reproduce both zero-field C and M data, thus placing Ce4Pt12Sn25 in the weak exchange coupling J < J(c) limit of the Doniach diagram, with a very small Kondo scale T-K << T-N. Magnetic field suppresses the AFM state at H* approximate to 0.7 T, much more effectively than expected from the Heisenberg model, indicating additional effects possibly due to frustration or residual Kondo screening.

【 授权许可】

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