Single-End Adaptive Optics Compensation for Emulated Turbulence in a Bi-Directional 10-Mbit/s per Channel Free-Space Quantum Communication Link Using Orbital-Angular-Momentum Encoding
Abstract
A single-end adaptive-optics (AO) module is experimentally demonstrated to mitigate the emulated atmospheric turbulence effects in a bi-directional quantum communication link, which employs orbital angular momentum (OAM) for data encoding. A classical Gaussian beam is used as a probe to detect the turbulence-induced wavefront distortion in the forward direction of the link. Based on the detected wavefront distortion, an AO system located on one end of the link is used to simultaneously compensate for the forward and backward channels. Specifically, with emulated turbulence and when the probe is turned on, the mode purity of photons carrying OAM l = 1 is improved by ~ 21 % with AO mitigation. We also measured the performance when encoding data using OAM { l = - 1 , + 2 } and { l = - 2 , + 1 } in the forward and backward channels, respectively, at 10 Mbit/s per channel with one photon per pulse on average. For this case, we found that the AO system could reduce the turbulence effects increased quantum-symbol-error-rate (QSER) by ~ 76 % and ~ 74 %, for both channels in the uni-directional and bi-directional cases, respectively. Similar QSER improvement is observed for the opposite direction channels in the bi-directional case.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Jan 01, 2019
- Source ID
- 10.34133/2019/8326701
Entities
People
- Alan E. Willner
- Ari N. Willner
- Cong Liu
- Guodong Xie
- Hao Song
- Haoqian Song
- Jeffrey H Shapiro
- Jiapeng Zhao
- Jing Du
- Kai Pang
- Long Li
- Moshe Tur
- Peicheng Liao
- Robert W. Boyd
- Runzhou Zhang
- Seyed M. H. Rafsanjani
- Yifan Zhao
- Yinwen Cao
- Yongxiong Ren
- Zhe Zhao
Organizations
- Massachusetts Institute of Technology
- National Science Foundation
- Office of Naval Research
- Tel Aviv University
- University of Rochester
- University of Southern California