The complex interactions between orbital angular momentum (OAM) light and atoms are particularly intriguing in the areas of quantum optics and quantum information science. Building a versatile high-dimensional quantum network needs broad spiral-bandwidth for preparing higher-quanta OAM mode and resolving the bandwidth mismatch in spatial space and etc. Here, we experimentally demonstrate a broad spiral-bandwidth quantum interface between photon and memory. Through twisted fields of the writing and reading, the correlated OAM distribution between photon and memory is significantly broadened. This broad spiral-bandwidth quantum interface could be spanned in multiplexing regime and could work in high-quanta scenario with capability of |l|=30, and we demonstrate the entanglement within 2-D subspace with a fidelity of 80.5\text{\textpm}4.8\% for high l. Such state-of-the-art technology to freely control the spatial distribution of OAM memory is very helpful to construct high-dimensional quantum networks and provides a benchmark in the field of actively developing methods to engineer OAM single photon from matters.
@article{arxiv.1806.10407,
title = {Broad Spiral-Bandwidth of Orbital Angular Momentum Interface between Photon and Memory},
author = {Dong-Sheng Ding and Ming-Xin Dong and Wei Zhang and Shuai Shi and Yi-Chen Yu and Ying-Hao Ye and Guang-Can Guo and Bao-Sen Shi},
journal= {arXiv preprint arXiv:1806.10407},
year = {2019}
}