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Purely electronic model for exciton-polaron formation in moiré heterostructures

Fabian Pichler1,2,*, Mohammad Hafezi3, and Michael Knap1,2

  • *Contact author: fabian.pichler@tum.de
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Phys. Rev. Research 8, 023140 – Published 11 May, 2026

DOI: https://doi.org/10.1103/98wg-qcfn

Abstract

Understanding interactions between excitons and correlated electronic states presents a fundamental challenge in quantum many-body physics. Here, we introduce a purely electronic model for the formation of exciton polarons in moiré lattices. Unlike conventional approaches that treat excitons as tightly bound bosonic particles, our model considers only electronic degrees of freedom, describing excitons as electron-hole bound states. Our findings reveal a pronounced renormalization of the polaron mass as a function of electron density, particularly near correlated insulators, consistent with recent transport experiments. Additionally, we predict an observable sign change in the effective polaron mass when increasing the electron density that can be measured in Hall-type experiments. Our purely electronic model provides a unified framework to investigate the formation and renormalization of exciton polarons in correlated states.

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Phys. Rev. Research 8, 023140– Published 11 May, 2026
  • Received 10 March 2025
  • Accepted 17 April 2026
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