Quantum criticality and inhomogeneous magnetic order in Fe-doped alpha-YbAlB4

Article

关键词: MUON SPIN RELAXATION;    FERMI-LIQUID BEHAVIOR;    SYSTEM BETA-YBALB4;    POSITIVE MUONS;    METALS;    FIELD;    INSTABILITIES;    CU;   

DOI  :  10.1103/PhysRevB.93.214421

来源: SCIE

【 摘 要 】

The intermediate-valent polymorphs alpha- and beta-YbAlB4 exhibit quantum criticality and other novel properties not usually associated with intermediate valence. Iron doping induces quantum criticality in alpha-YbAlB4 and magnetic order in both compounds. We report results of muon spin relaxation (mu SR) experiments in alpha-YbAl(1-x)Fex B-4, x = 0.014 and 0.25. For x = 0.014 we find no evidence for magnetic order down to 25 mK. The dynamic muon spin relaxation rate.d exhibits a power-law temperature dependence lambda(d) proportional to T-a, a = 0.40(4), in the temperature range 100 mK-2 K, in disagreement with predictions by theories of antiferromagnetic (AFM) or valence quantum critical behavior. For x = 0.25, where AFM order develops in the temperature range 7.5-10 K, we find coexistence of meso-ormacroscopically segregated paramagnetic and AFM phases, with considerable disorder in the latter down to 2 K.

【 授权许可】

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