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Orbital Disordering and metal-insulator transition with hole-doping in perovskite-type vanadium oxides

J. Fujioka·S. Miyasaka·Y. Tokura
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Abstract

Filling-control metal-insulator transitions (MITs) and related electronic phase diagrams have been investigated for hole-doped vanadium oxides, Pr_{1-x}Ca_xVO_3, Nd_{1-x}Sr_xVO_3 and Y_{1-x}Ca_xVO_3, with perovskite structure. The increase of the doping level x causes the melting of the G-type (and C-type) orbital order, prior to or concomitantly with the MIT, due partly to the doped-hole motion and partly to the ramdom potential arising from the quenched disorder. In particular, the G-type spin- and C-type orbital-ordered phase present in Y_{1-x}Ca_xVO_3 disappears immediately upon hole doping, around x=0.02. On the other hand, the critical doping level x for MIT is governed by the electron-correlation strength of the undoped parent compound.

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J. Fujioka, S. Miyasaka, Y. Tokura. 2005-05-08. Orbital Disordering and metal-insulator transition with hole-doping in perovskite-type vanadium oxides. https://doi.org/10.1103/physrevb.72.024460

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