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arXiv · 2405.17539

Emergent Gauge Fields in Band Insulators

Zhaoyu Han·Steven Kivelson
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Abstract

By explicit microscopic construction involving a mapping to a quantum vertex model subject to the `ice rule,' we show that an electronically `trivial' band insulator with suitable vibrational (phonon) degrees of freedom can host a ``resonating valence-bond'' state - a quantum phase with emergent gauge fields. This novel type of band insulator is identifiable by the existence of emergent gapless `photon' modes and deconfined excitations, the latter of which carry non-quantized mobile charges. We suggest that such phases may exist in the quantum regimes of various nearly ferroelectric materials.

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Zhaoyu Han, Steven Kivelson. 2024-05-27. Emergent Gauge Fields in Band Insulators. https://doi.org/10.1073/pnas.2421778122

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