High-dimensional entanglement generation based on a Pancharatnam–Berry phase metasurface
Zhixiang Li, Zhu Dong, Peicheng Lin, Pengcheng Huo, Hongkuan Xia, Mingze Liu, Ya-Ping Ruan, Jiang-Shan Tang, Miao Cai, Haodong Wu, Chaoying Meng, Han Zhang, Peng Chen, Ting Xu, Keyu Xia, Lijian Zhang, Yanqing Lu
Abstract
High-dimensional entanglement is of great importance in quantum communications and can be realized by encoding information on multiple degrees of freedom (DoFs) of the photons. Conventionally, the realization of such high-dimensional entanglement involves different combinations of bulky optical elements. In this work, we present the use of a single dielectric metasurface to generate high-dimensional entanglement by modulating multi-DoFs of photons. By sending one of the polarization-entangled photons to interact with the metasurface, we encode path, spin angular momentum, and orbital angular momentum information to the original state. We achieve a four-qubit quantum state in the experiment. To verify it, we experimentally demonstrate the nonlocal correlations between the two photons by recording the correlated images, and we also perform a quantum state tomography measurement. This scheme can be applied to on-chip quantum state manipulation, which is promising in quantum communication with integrated components.