Integer Quantum Magnon Hall Plateau-Plateau Transition in a Spin Ice Model

TL;DR

This paper demonstrates a quantum phase transition in a disordered two-dimensional spin ice model, where magnon bands transition from an integer quantum magnon Hall regime to a localized regime, with critical behavior similar to quantum Hall transitions.

Contribution

It introduces the concept of integer quantum magnon Hall effect in a spin ice model and analyzes the disorder-induced phase transition using finite size scaling and conductance distribution.

Findings

Magnon bands exhibit a transition from quantum Hall to localized regime due to disorder.

Critical conductance distribution indicates universality class similar to quantum Hall transition.

Thermal magnon Hall conductivity is characterized by robust chiral edge magnon transport.

Abstract

Low-energy magnon bands in a two-dimensional spin ice model become integer quantum magnon Hall bands. By calculating the localization length and the two-terminal conductance of magnon transport, we show that the magnon bands with disorders undergo a quantum phase transition from an integer quantum magnon Hall regime to a conventional magnon localized regime. Finite size scaling analysis as well as a critical conductance distribution shows that the quantum critical point belongs to the same universality class as that in the quantum Hall transition. We characterize thermal magnon Hall conductivity in disordered quantum magnon Hall system in terms of robust chiral edge magnon transport.