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

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

Rongwei Hu (胡荣伟), Kefeng Wang (王克锋), Hyejin Ryu (류혜진), Hechang Lei (雷和畅), E. S. Choi, M. Uhlarz, J. Wosnitza, and C. Petrovic

Phys. Rev. Lett. 109, 256401 – Published 17 December 2012

Abstract

We report on the emergence of an electronic Griffiths phase in the doped semiconductor ${FeSb}_{2}$ , predicted for disordered insulators with random localized moments in the vicinity of a metal-insulator transition. 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 electronic Griffiths phase states are found on the metallic boundary between the insulating state ( $x = 0$ ) and a long-range albeit weak magnetic order ( $x \geq 0.075$ ).

Received 10 September 2012

DOI:https://doi.org/10.1103/PhysRevLett.109.256401

Authors & Affiliations

Rongwei Hu (胡荣伟)^1,*, Kefeng Wang (王克锋)¹, Hyejin Ryu (류혜진)¹, Hechang Lei (雷和畅)¹, E. S. Choi², M. Uhlarz³, J. Wosnitza³, and C. Petrovic^1,†

¹Condensed Matter Physics and Materials Science Department, Brookhaven National Laboratory, Upton, New York 11973, USA
²NHMFL/Physics, Florida State University, Tallahassee, Florida 32310, USA
³Hochfeld-Magnetlabor Dresden (HLD), Helmholtz-Zentrum Dresden-Rossendorf, D-01314 Dresden, Germany

^*Present address: Department of Physics, University of Maryland, College Park, MD 20742-4111, USA.
^†petrovic@bnl.gov