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arXiv · 1507.03105

Insulator/metal phase transition and colossal magnetoresistance in holographic model

Rong-Gen Cai·Run-Qiu Yang
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Abstract

Within massive gravity, we construct a gravity dual for insulator/metal phase transition and colossal magnetoresistance (CMR) effect found in some manganese oxides materials. In heavy graviton limit, a remarkable magnetic-field-sensitive DC resistivity peak appears at the Curie temperature, where an insulator/metal phase transition happens and the magnetoresistance is scaled with the square of field-induced magnetization. We find that metallic and insulating phases coexist below the Curie point and the relation with the electronic phase separation is discussed.

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Rong-Gen Cai, Run-Qiu Yang. 2015-07-27. Insulator/metal phase transition and colossal magnetoresistance in holographic model. https://doi.org/10.1103/physrevd.92.106002

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