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First order transition from correlated electron semiconductor to ferromagnetic metal in single crystalline FeSi1-xGex

S. Yeo·S. Nakatsuji·A. D. Bianchi·P. Schlottmann·Z. Fisk·L. Balicas·P. A. Stampe·R. J. Kennedy
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Abstract

The phase diagram of FeSi1-xGex, obtained from magnetic, thermal and transport measurements on single crystals, shows a first-order transition from a correlated electron semiconductor to a ferromagnetic metal at a critical concentration, x ~ 0.25. The gap of the insulating phase strongly decreases with x. The specific heat coefficient appears to track the density of states of a Kondo insulator. The phase diagram is consistent with a correlation induced insulator-metal transition in conjunction with disorder on the Si/Ge ligand site.

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S. Yeo, S. Nakatsuji, A. D. Bianchi, P. Schlottmann, Z. Fisk, L. Balicas, P. A. Stampe, R. J. Kennedy. 2003-02-24. First order transition from correlated electron semiconductor to ferromagnetic metal in single crystalline FeSi1-xGex. https://doi.org/10.1103/physrevlett.91.046401

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