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arXiv · 2006.07963

Protecting Quantum Superposition and Entanglement with Photonic Higher-Order Topological Crystalline Insulator

Yao Wang·Bi-Ye Xie·Yong-Heng Lu·Yi-Jun Chang·Hong-Fei Wang·Jun Gao·Zhi-Qiang Jiao·Zhen Feng·Xiao-Yun Xu·Feng Mei·Suotang Jia·Ming-Hui Lu·Xian-Min Jin
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Abstract

Higher-order topological insulator, as a newly found non-trivial material and structure, possesses a topological phase beyond the bulk-boundary correspondence. Here, we present an experimental observation of photonic higher-order topological crystalline insulator and its topological protection to quantum superposition and entanglement in a two-dimensional lattice. By freely writing the insulator structure with femtosecond laser and directly measuring evolution dynamics with single-photon imaging techniques, we are able to observe the distinct features of the topological corner states in C_4 and C_2 photonic lattice symmetry. Especially, we propose and experimentally identify the topological corner states by exciting the photonic lattice with single-photon superposition state, and we examine the protection impact of topology on quantum entanglement for entangled photon states. The single-photon dynamics and the protected entanglement reveal an intrinsic topological protection mechanism isolating multi-partite quantum states from diffusion-induced decoherence. The higher-order topological crystalline insulator, built-in superposition state generation, heralded single-photon imaging and quantum entanglement demonstrated here link topology, material, and quantum physics, opening the door to wide investigations of higher-order topology and applications of topological enhancement in genuine quantum regime.

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Yao Wang, Bi-Ye Xie, Yong-Heng Lu, Yi-Jun Chang, Hong-Fei Wang, Jun Gao, Zhi-Qiang Jiao, Zhen Feng, Xiao-Yun Xu, Feng Mei, Suotang Jia, Ming-Hui Lu, Xian-Min Jin. 2020-06-14. Protecting Quantum Superposition and Entanglement with Photonic Higher-Order Topological Crystalline Insulator. https://arxiv.org/abs/2006.07963

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