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

Cong Liu; Kai Pang; Zhe Zhao; Peicheng Liao; Runzhou Zhang; Haoqian Song; Yinwen Cao; Jing Du; Long Li; Hao Song; Yongxiong Ren; Guodong Xie; Yifan Zhao; Jiapeng Zhao; Seyed M. H. Rafsanjani; Ari N. Willner; Jeffrey H. Shapiro; Robert W. Boyd; Moshe Tur; Alan E. Willner

doi:10.34133/2019/8326701

Research (Jan 2019)

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

Cong Liu,
Kai Pang,
Zhe Zhao,
Peicheng Liao,
Runzhou Zhang,
Haoqian Song,
Yinwen Cao,
Jing Du,
Long Li,
Hao Song,
Yongxiong Ren,
Guodong Xie,
Yifan Zhao,
Jiapeng Zhao,
Seyed M. H. Rafsanjani,
Ari N. Willner,
Jeffrey H. Shapiro,
Robert W. Boyd,
Moshe Tur,
Alan E. Willner

Affiliations

Cong Liu: Department of Electrical Engineering, University of Southern California, Los Angeles, CA 90089, USA; Department of Physics and Astronomy, University of Southern California, Los Angeles, CA 90089, USA
Kai Pang: Department of Electrical Engineering, University of Southern California, Los Angeles, CA 90089, USA
Zhe Zhao: Department of Electrical Engineering, University of Southern California, Los Angeles, CA 90089, USA
Peicheng Liao: Department of Electrical Engineering, University of Southern California, Los Angeles, CA 90089, USA
Runzhou Zhang: Department of Electrical Engineering, University of Southern California, Los Angeles, CA 90089, USA
Haoqian Song: Department of Electrical Engineering, University of Southern California, Los Angeles, CA 90089, USA
Yinwen Cao: Department of Electrical Engineering, University of Southern California, Los Angeles, CA 90089, USA
Jing Du: Department of Electrical Engineering, University of Southern California, Los Angeles, CA 90089, USA
Long Li: Department of Electrical Engineering, University of Southern California, Los Angeles, CA 90089, USA
Hao Song: Department of Electrical Engineering, University of Southern California, Los Angeles, CA 90089, USA
Yongxiong Ren: Department of Electrical Engineering, University of Southern California, Los Angeles, CA 90089, USA
Guodong Xie: Department of Electrical Engineering, University of Southern California, Los Angeles, CA 90089, USA
Yifan Zhao: Department of Electrical Engineering, University of Southern California, Los Angeles, CA 90089, USA
Jiapeng Zhao: The Institute of Optics, University of Rochester, Rochester, New York 14627, USA
Seyed M. H. Rafsanjani: The Institute of Optics, University of Rochester, Rochester, New York 14627, USA
Ari N. Willner: Department of Electrical Engineering, University of Southern California, Los Angeles, CA 90089, USA
Jeffrey H. Shapiro: Massachusetts Institute of Technology, Research Laboratory of Electronics, Cambridge, Massachusetts 02139, USA
Robert W. Boyd: The Institute of Optics, University of Rochester, Rochester, New York 14627, USA
Moshe Tur: School of Electrical Engineering, Tel Aviv University, Ramat Aviv 69978, Israel
Alan E. Willner: Department of Electrical Engineering, University of Southern California, Los Angeles, CA 90089, USA

DOI: https://doi.org/10.34133/2019/8326701
Journal volume & issue: Vol. 2019

Abstract

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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.

Published in Research

ISSN: 2096-5168 (Print); 2639-5274 (Online)
Publisher: American Association for the Advancement of Science (AAAS)
Country of publisher: United States
LCC subjects: Science
Website: https://spj.science.org/journal/research

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