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arXiv · 2303.08804

Electron-photon Chern number in cavity-embedded 2D moir\'e materials

Danh-Phuong Nguyen·Geva Arwas·Zuzhang Lin·Wang Yao·Cristiano Ciuti
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Abstract

We explore theoretically how the topological properties of 2D materials can be manipulated by cavity quantum electromagnetic fields for both resonant and off-resonant electron-photon coupling, with a focus on van der Waals moir\'e superlattices. We investigate an electron-photon topological Chern number for the cavity-dressed energy minibands that is well defined for any degree of hybridization of the electron and photon states. While an off-resonant cavity mode can renormalize electronic topological phases that exist without cavity coupling, we show that when the cavity mode is resonant to electronic miniband transitions, new and higher electron-photon Chern numbers can emerge.

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Danh-Phuong Nguyen, Geva Arwas, Zuzhang Lin, Wang Yao, Cristiano Ciuti. 2023-03-15. Electron-photon Chern number in cavity-embedded 2D moir\'e materials. https://doi.org/10.1103/physrevlett.131.176602

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