Insulator/metal phase transition and colossal magnetoresistance in holographic model

TL;DR

This paper develops a holographic model within massive gravity to simulate insulator/metal phase transitions and colossal magnetoresistance, capturing key experimental features like resistivity peaks and phase coexistence.

Contribution

It introduces a novel holographic framework for modeling phase transitions and CMR effects in manganese oxides using massive gravity.

Findings

Magnetic-field-sensitive resistivity peak at Curie temperature

Resistivity scales with square of magnetization

Coexistence of metallic and insulating phases below Curie point

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.