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arXiv · 2512.16651

Theory of exciton polarons in 2D Wigner crystals

Haydn S. Adlong·Eugen Dizer·Richard Schmidt·Atac Imamoglu·Arthur Christianen
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Abstract

Monolayer transition-metal dichalcogenides (TMDs) provide a platform for realizing Wigner crystals and enable their detection via exciton spectroscopy. We develop a microscopic theoretical model for excitons interacting with the localized electrons of the Wigner crystal, including their vibrational motion. In addition to the previously observed exciton-Umklapp feature, the theory reproduces and explains the higher-band attractive-polaron resonances recently reported experimentally. Our model further uncovers that the appearance of two equal-strength and parallel attractive polarons, as commonly observed in WSe$_2$ and WS$_2$, is a signature of strong correlations in the electronic system. Altogether, our results demonstrate that accounting for electronic interactions is essential to reproduce and interpret the exciton-polaron spectra of TMDs.

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Haydn S. Adlong, Eugen Dizer, Richard Schmidt, Atac Imamoglu, Arthur Christianen. 2025-12-18. Theory of exciton polarons in 2D Wigner crystals. https://arxiv.org/abs/2512.16651

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