Localized moments and the stability of antiferromagnetic order in Yb3Pt4

Article

关键词: QUANTUM CRITICAL-POINT;    HEAVY-FERMION METALS;    PHASE-TRANSITIONS;    CRITICALITY;    YBRH2SI2;    PRESSURE;    ANOMALIES;    ELECTRON;    DIAGRAM;    SURFACE;   

DOI  :  10.1103/PhysRevB.86.054401

来源: SCIE

【 摘 要 】

We present here the results of electrical resistivity rho, magnetization M, ac susceptibility chi(ac)', and specific heat C-M measurements that have been carried out on single crystals of Yb3Pt4 over a wide range of fields and temperatures. The 2.4-K Neel temperature that is found in zero field collapses under field to a first-order transition T-N = 0 at B-CEP = 1.85 T. In the absence of antiferromagnetic order, the specific heat C-M(T, B), the magnetization M(T, B), and even the resistivity rho(T, B) all display B/T scaling, indicating that they are dominated by strong paramagnetic fluctuations, where the only characteristic energy scale results from the Zeeman splitting of an energetically isolated, Yb doublet ground state. This paramagnetic scattering disappears with the onset of antiferromagnetic order, revealing Fermi liquid behavior Lambda rho = AT(2) that persists up to the antiferromagnetic phase line T-N(B), but not beyond. The first-order character of T-N = 0 and the ubiquity of the paramagnetic fluctuations imply that non-Fermi-liquid behaviors are absent in Yb3Pt4. In contrast to heavy fermions such as YbRh2Si2, Yb3Pt4 represents an extremely simple regime of f-electron behavior where the Yb moments and conduction electrons are almost decoupled, and where Kondo physics plays little role.

【 授权许可】

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