Electrostatics-induced breakdown of the integer quantum Hall effect in cavity QED

TL;DR

This paper investigates the breakdown of the integer quantum Hall effect in a 2D electron gas within a cavity, proposing a new electrostatic boundary effect mechanism supported by a minimal model.

Contribution

It introduces a novel electrostatic boundary effect mechanism explaining the quantum Hall breakdown, supported by a minimal single-electron model matching experimental signatures.

Findings

Predicted signatures align with experimental observations.

Electrostatic boundary effects can induce non-chiral edge channels.

Mechanism distinguishes itself from purely vacuum-induced explanations.

Abstract

We analyze the recently observed breakdown of the integer quantum Hall effect in a two-dimensional electron gas embedded in a metallic split-ring resonator. By accounting for both the quantized vacuum field and electrostatic boundary modifications, we identify a mechanism that could potentially explain this breakdown in terms of non-chiral edge channels arising from electrostatic boundary effects. For experimentally relevant geometries, a minimal single-electron model of this mechanism predicts characteristic signatures and energy scales consistent with those observed in experiments. These predictions can be directly tested against alternative, purely vacuum-induced explanations to shed further light on the origin of this puzzling phenomenon.