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arXiv · 2209.05275

Observation of Floquet topological phases with large Chern numbers

Kai Yang·Shaoyi Xu·Longwen Zhou·Zhiyuan Zhao·Tianyu Xie·Zhe Ding·Wenchao Ma·Jiangbin Gong·Fazhan Shi·Jiangfeng Du
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Abstract

One of the most intriguing advantage of Floquet engineering is to generate new phases with large topological invariants. In this work, we experimentally simulate a periodically quenched generalized Haldane model on an NV center in diamond, and observe its Floquet Chern insulator phases with Chern numbers $C=1,2,4$ by imaging the static and dynamic spin textures in momentum space. Our work reveals the power of Floquet driving in transforming system's topology and generating large Chern number phases. It further establishes a unique experimental scheme to detect Floquet topological phases in two and higher spatial dimensions.

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Kai Yang, Shaoyi Xu, Longwen Zhou, Zhiyuan Zhao, Tianyu Xie, Zhe Ding, Wenchao Ma, Jiangbin Gong, Fazhan Shi, Jiangfeng Du. 2022-09-12. Observation of Floquet topological phases with large Chern numbers. https://doi.org/10.1103/physrevb.106.184106

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