Tang Ruikai, Li Xiongjie, Wu Wenjie, Pan Haifeng, Zeng Heping, Wu E
Opt Express. 2015 Apr 20;23(8):9796-802. doi: 10.1364/OE.23.009796.
The orbital angular momentum (OAM) of light shows great potential in quantum communication. The transmission wavelength for telecom is usually around 1550 nm, while the common quantum information storage and processing devices based on atoms, ions or NV color centers are for photons in visible regime. Here we demonstrate a quantum information interface based on the frequency upconversion for photons carrying OAM states from telecom wavelength to visible regime by sum-frequency generation with high quantum conversion efficiency. The infrared photons at 1558 nm carrying different OAM values were converted to the visible regime of 622.2 nm, and the OAM value of the signal photons was well preserved in the frequency upconversion process with pump beam in Gaussian profile.
光的轨道角动量（OAM）在量子通信中显示出巨大潜力。电信传输波长通常在1550纳米左右，而基于原子、离子或NV色心的常见量子信息存储和处理设备则用于可见光波段的光子。在此，我们展示了一种基于频率上转换的量子信息接口，通过和频产生，以高量子转换效率将携带OAM态的光子从电信波长转换到可见光波段。携带不同OAM值的1558纳米红外光子被转换到622.2纳米的可见光波段，并且在泵浦光束为高斯分布的频率上转换过程中，信号光子的OAM值得到了很好的保留。
