Experimental one-step deterministic polarization entanglement purification

Cen-Xiao Huang; Xiao-Min Hu; Bi-Heng Liu; Lan Zhou; Yu-Bo Sheng; Chuan-Feng Li; Guang-Can Guo

doi:10.1016/j.scib.2021.12.018

Experimental one-step deterministic polarization entanglement purification

Sci Bull (Beijing). 2022 Mar 30;67(6):593-597. doi: 10.1016/j.scib.2021.12.018. Epub 2021 Dec 27.

Authors

Cen-Xiao Huang¹, Xiao-Min Hu¹, Bi-Heng Liu², Lan Zhou³, Yu-Bo Sheng⁴, Chuan-Feng Li⁵, Guang-Can Guo⁶

Affiliations

¹ CAS Key Laboratory of Quantum Information, University of Science and Technology of China, Hefei 230026, China; Synergetic Innovation Center of Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei 230026, China.
² CAS Key Laboratory of Quantum Information, University of Science and Technology of China, Hefei 230026, China; Synergetic Innovation Center of Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei 230026, China. Electronic address: bhliu@ustc.edu.cn.
³ School of Science, Nanjing University of Posts and Telecommunications, Nanjing 210003, China; Institute of Quantum Information and Technology, Nanjing University of Posts and Telecommunications, Nanjing 210003, China.
⁴ College of Electronic and Optical Engineering, Nanjing University of Posts and Telecommunications, Nanjing 210003, China; Institute of Quantum Information and Technology, Nanjing University of Posts and Telecommunications, Nanjing 210003, China. Electronic address: shengyb@njupt.edu.cn.
⁵ CAS Key Laboratory of Quantum Information, University of Science and Technology of China, Hefei 230026, China; Synergetic Innovation Center of Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei 230026, China. Electronic address: cfli@ustc.edu.cn.
⁶ CAS Key Laboratory of Quantum Information, University of Science and Technology of China, Hefei 230026, China; Synergetic Innovation Center of Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei 230026, China; Institute of Quantum Information and Technology, Nanjing University of Posts and Telecommunications, Nanjing 210003, China.

PMID: 36546120
DOI: 10.1016/j.scib.2021.12.018

Abstract

Entanglement purification is to distill high-quality entangled states from low-quality entangled states. It is a key step in quantum repeaters, determines the efficiency and communication rates of quantum communication protocols, and is hence of central importance in long-distance communications and quantum networks. In this work, we report the first experimental demonstration of deterministic entanglement purification using polarization and spatial mode hyperentanglement. After purification, the fidelity of polarization entanglement arises from 0.268±0.002 to 0.989±0.001. Assisted with robust spatial mode entanglement, the total purification efficiency can be estimated as 10⁹ times that of the entanglement purification protocols using two copies of entangled states when one uses the spontaneous parametric down-conversion sources. Our work may have the potential to be implemented as a part of full repeater protocols.

Keywords: Deterministic entanglement purification; Hyperentanglement; Quantum communication; Quantum entanglement; Quantum repeater.