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

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 نشر من قبل Cedomir Petrovic
 تاريخ النشر 2016
  مجال البحث فيزياء
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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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