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arXiv · 1703.07793

A model for continuous thermal Metal to Insulator Transition

Chao-Ming Jian·Zhen Bi·Cenke Xu
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Abstract

We propose a $d-$dimensional interacting Majorana fermion model with quenched disorder, which gives us a continuous quantum phase transition between a diffusive thermal metal phase with a finite entropy density to an insulator phase with zero entropy density. This model is based on coupled Sachdev-Ye-Kitaev model clusters, and hence has a controlled large-$N$ limit. The metal-insulator transition is accompanied by a spontaneous time-reversal symmetry breaking. We perform controlled calculations to show that the diffusion constant jumps to zero discontinuously at the metal-insulator transition, while the time-reversal symmetry breaking order parameter increases continuously.

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Chao-Ming Jian, Zhen Bi, Cenke Xu. 2017-03-22. A model for continuous thermal Metal to Insulator Transition. https://doi.org/10.1103/physrevb.96.115122

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