Emergent Haldane Model and Photon-Valley Locking in Chiral Cavities

Liu Yang; Qing-Dong Jiang

doi:10.1038/s42005-025-02060-x

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arXiv · 2403.11063

Emergent Haldane Model and Photon-Valley Locking in Chiral Cavities

Liu Yang·Qing-Dong Jiang

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Abstract

The realization of Haldane's topological graphene model in practical materials has presented significant challenges. Here, we propose achieving this model by embedding graphene in chiral cavities, using the asymptotically decoupled framework detailed in Ref. [Phys. Rev. Lett. 126, 153603 (2021)]. Additionally, we introduce an equilibrium strategy for achieving valley polarization in this system with C2-symmetry breaking. Through numerical methods, we quantify the locking of photon numbers with Bloch electrons and calculate the topology-induced imbalance of valley photons. Furthermore, we elucidate that topological phase transition is characterized by the sign change of photon numbers during interband excitation. These findings underscore the remarkable potential of utilizing cavity quantum fluctuations to engineer electronic and photonic properties specific to valleys and topologies, particularly within the realm of strong light-matter coupling.

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Liu Yang, Qing-Dong Jiang. 2024-03-17. Emergent Haldane Model and Photon-Valley Locking in Chiral Cavities. https://doi.org/10.1038/s42005-025-02060-x

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