Abstract

In this paper, we demonstrate the generation of high-performance entangled photon-pairs in different degrees of freedom from a single piece of fiber pigtailed periodically poled LiNbO3 (PPLN) waveguide. We utilize cascaded second-order nonlinear optical processes, i.e., second-harmonic generation (SHG) and spontaneous parametric downconversion (SPDC), to generate photon-pairs. Previously, the performance of the photon-pairs is contaminated by Raman noise photons. Here by fiber-integrating the PPLN waveguide with noise-rejecting filters, we obtain a coincidence-to-accidental ratio (CAR) higher than 52,600 with photon-pair generation and detection rate of 52.36 kHz and 3.51 kHz, respectively. Energy-time, frequency-bin, and time-bin entanglement is prepared by coherently superposing correlated two-photon states in these degrees of freedom, respectively. The energy-time entangled two-photon states achieve the maximum value of CHSH-Bell inequality of S = 2.71 ± 0.02 with two-photon interference visibility of 95.74 ± 0.86%. The frequency-bin entangled two-photon states achieve fidelity of 97.56 ± 1.79% with a spatial quantum beating visibility of 96.85 ± 2.46%. The time-bin entangled two-photon states achieve the maximum value of CHSH-Bell inequality of S = 2.60 ± 0.04 and quantum tomographic fidelity of 89.07 ± 4.35%. Our results provide a potential candidate for the quantum light source in quantum photonics.

Details

Title
High-performance quantum entanglement generation via cascaded second-order nonlinear processes
Author
Zhang Zichang 1 ; Yuan Chenzhi 1   VIAFID ORCID Logo  ; Shen, Si 1 ; Yu, Hao 1 ; Zhang, Ruiming 1 ; Wang Heqing 2 ; Li, Hao 2 ; Wang, You 3 ; Deng Guangwei 4 ; Wang, Zhiming 5 ; You Lixing 2   VIAFID ORCID Logo  ; Wang, Zhen 2 ; Song Haizhi 3 ; Guo Guangcan 6 ; Zhou, Qiang 4   VIAFID ORCID Logo 

1  University of Electronic Science and Technology of China, Institute of Fundamental and Frontier Sciences, Chengdu, China (GRID:grid.54549.39) (ISNI:0000 0004 0369 4060); University of Electronic Science and Technology of China, Yangtze Delta Region Institute (Huzhou) & School of Optoelectronic Science and Engineering, Huzhou, China (GRID:grid.54549.39) (ISNI:0000 0004 0369 4060) 
2  Chinese Academy of Sciences, Shanghai Institute of Microsystem and information Technology, Shanghai, China (GRID:grid.9227.e) (ISNI:0000000119573309) 
3  University of Electronic Science and Technology of China, Institute of Fundamental and Frontier Sciences, Chengdu, China (GRID:grid.54549.39) (ISNI:0000 0004 0369 4060); Southwest Institute of Technical Physics, Chengdu, China (GRID:grid.54549.39) 
4  University of Electronic Science and Technology of China, Institute of Fundamental and Frontier Sciences, Chengdu, China (GRID:grid.54549.39) (ISNI:0000 0004 0369 4060); University of Electronic Science and Technology of China, Yangtze Delta Region Institute (Huzhou) & School of Optoelectronic Science and Engineering, Huzhou, China (GRID:grid.54549.39) (ISNI:0000 0004 0369 4060); University of Science and Technology of China, CAS Key Laboratory of Quantum Information, Hefei, China (GRID:grid.59053.3a) (ISNI:0000000121679639) 
5  University of Electronic Science and Technology of China, Institute of Fundamental and Frontier Sciences, Chengdu, China (GRID:grid.54549.39) (ISNI:0000 0004 0369 4060); Southern University of Science and Technology, Shenzhen Institute for Quantum Science and Engineering, Shenzhen, China (GRID:grid.263817.9) 
6  University of Electronic Science and Technology of China, Institute of Fundamental and Frontier Sciences, Chengdu, China (GRID:grid.54549.39) (ISNI:0000 0004 0369 4060); University of Science and Technology of China, CAS Key Laboratory of Quantum Information, Hefei, China (GRID:grid.59053.3a) (ISNI:0000000121679639) 
Publication year
2021
Publication date
2021
Publisher
Nature Publishing Group
e-ISSN
20566387
Source type
Scholarly Journal
Language of publication
English
DOI
https://doi.org/10.1038/s41534-021-00462-7
ProQuest document ID
2558266532
Copyright
© The Author(s) 2021. This work is published under http://creativecommons.org/licenses/by/4.0/ (the “License”). Notwithstanding the ProQuest Terms and Conditions, you may use this content in accordance with the terms of the License.