中文摘要：

轨道角动量（OAM）光束在精密测量、微小粒子的操控以及基础物理研究等领域具有重要的应用,同时基于OAM编码的光信息处理由于其信道容量大、保密性高等优点已成为经典和量子通信领域的研究热点.基于OAM编码构建高维量子网络是目前量子信息领域的一个重要研究方向,在近几年已取得了许多突破性进展.在量子通信中,作为信息载体的光子需要在低损耗的通信窗口传输,而作为信息存储和处理单元的物理体系其工作波长一般却不在通信窗口,因此需要在两者之间建立量子接口以满足量子信息既可被存储又能长距离传输的基本要求.基于非线性过程的光子频率变换就是建立量子接口的一种行之有效的方法.本文在概述了OAM光束频率变换的发展现状后,着重介绍了量子条件下OAM光子的频率变换研究进展.这些进展迈出了未来构建高维量子信息网络的重要一步.

英文摘要：

Light carrying orbital angular momentum（OAM） has exciting applications, including the studies of fundamental quantum physics, optical manipulation and trapping of particles, astrophysics, high-precision optical measurements and optical communication, etc. In quantum information field, a photon encoded with information in its OAM degrees of freedom enables networks to carry significantly more information and increase their capacity greatly due to the inherent infinite degrees of freedom for OAM. Therefore it is no surprise that many groups and researchers are active in building up a high-dimensional quantum network and many important progresses have been achieved during the past years. To realize a long-distance quantum communication, a quantum repeater has to be used to overcome the problem of communication fidelity decreasing exponentially with the channel length, where, quantum memories for photons, used for storing quantum information, which have been realized successfully during the past decade in many systems such as a cold/hot atomic system, a solid matter, a diamond, and others, are key components consisting of a quantum repeater. Photons acted as information candidates can connect different quantum repeaters. Long distance quantum communication requires the wavelengths of photons are situated in the low-loss communication windows, but most quantum memories currently being developed for use in a quantum repeater work at different wavelengths, only few memories can work in low-loss communication windows. Furthermore, the signal stored is an attenuated coherent light and has the Gaussian mode. Though the storage of photonic entanglement at telecom wavelength is realized in an erbium-doped optical fibre recently, the spatial mode used is Gaussian mode. Quantum memories for photons with OAM have recently been realized, but all work at different wavelengths. So a quantum interface to bridge the wavelength gap is necessary. There are some experimental realizations of quantum interfaces for single photons wit