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arXiv · 1604.02139

Electronic Griffiths Phase in the Te - Doped Semiconductor FeSb$_{2}$

Rongwei Hu·Kefeng Wang·Hyejin Ryu·Hechang Lei·E. S. Choi·M. Uhlarz·J. Wosnitza·C. Petrovic
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Abstract

We report on the emergence of an Electronic Griffiths Phase (EGP) in the doped semiconductor FeSb$_{2}$, predicted for disordered insulators with random localized moments in the vicinity of a metal-insulator transition (MIT). Magnetic, transport, and thermodynamic measurements of Fe(Sb$_{1-x}$Te$_{x}$)$_{2}$ single crystals show signatures of disorder-induced non-Fermi liquid behavior and a Wilson ratio expected for strong electronic correlations. The EGP states are found on the metallic boundary, between the insulating state ($x = 0$) and a long-range albeit weak magnetic order ($x \geq 0.075$).

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Rongwei Hu, Kefeng Wang, Hyejin Ryu, Hechang Lei, E. S. Choi, M. Uhlarz, J. Wosnitza, C. Petrovic. 2016-04-07. Electronic Griffiths Phase in the Te - Doped Semiconductor FeSb$_{2}$. https://doi.org/10.1103/physrevlett.109.256401

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