Topological quantum phase transition in magnetic topological insulator upon magnetization rotation

TL;DR

This paper investigates a continuous topological phase transition in a magnetic topological insulator driven by magnetization rotation, revealing critical behavior and a percolation mechanism of edge channels.

Contribution

It demonstrates a magnetization-induced phase transition between quantum anomalous Hall and trivial insulator phases with critical behavior analysis.

Findings

Hall conductivity transitions from quantized to zero

Transition curves cross at a single point at various temperatures

Critical exponent of the transition slope is -0.61

Abstract

We report a continuous phase transition between quantum-anomalous-Hall and trivial-insulator phases in a magnetic topological insulator upon magnetization rotation. The Hall conductivity transits from one plateau of quantized Hall conductivity $e^2/h$ to the other plateau of zero Hall conductivity. The transition curves taken at various temperatures cross almost at a single point, exemplifying the critical behavior of the transition. The slope of the transition curves follows a power-law temperature dependence with a critical exponent of $-0.61$. This suggests a common underlying origin in the plateau transitions between the QAH and quantum Hall systems, which is a percolation of one-dimensional chiral edge channels.