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arXiv · 2310.10365

Berry Curvature and Bulk-Boundary Correspondence from Transport Measurement for Photonic Chern Bands

Abstract

Berry curvature is a fundamental element to characterize topological quantum physics, while a full measurement of Berry curvature in momentum space was not reported for topological states. Here we achieve two-dimensional Berry curvature reconstruction in a photonic quantum anomalous Hall system via Hall transport measurement of a momentum-resolved wave packet. Integrating measured Berry curvature over the two-dimensional Brillouin zone, we obtain Chern numbers corresponding to -1 and 0. Further, we identify bulk-boundary correspondence by measuring topology-linked chiral edge states at the boundary. The full topological characterization of photonic Chern bands from Berry curvature, Chern number, and edge transport measurements enables our photonic system to serve as a versatile platform for further in-depth study of novel topological physics.

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Chao Chen, Run-Ze Liu, Jizhou Wu, Zu-En Su, Xing Ding, Jian Qin, Lin Wang, Wei-Wei Zhang, Yu He, Xi-Lin Wang, Chao-Yang Lu, Li Li, Barry C. Sanders, Xiong-Jun Liu, Jian-Wei Pan. 2023-10-16. Berry Curvature and Bulk-Boundary Correspondence from Transport Measurement for Photonic Chern Bands. https://doi.org/10.1103/physrevlett.131.133601

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