Open AccessCounterpropagating path-entangled photon pair sources based on simultaneous spontaneous parametric down-conversion processes of nonlinear photonic crystal
Author(s) -
Can Yang,
Chaoxiang Xi,
Jietai Jing,
Guangqiang He
Publication year - 2018
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.26.027945
Subject(s) - spontaneous parametric down conversion , physics , quantum entanglement , photon entanglement , photon , nonlinear photonic crystal , quantum optics , optics , optical path , lithium niobate , photonic crystal , quantum key distribution , parametric statistics , photonics , quantum , nonlinear optics , quantum mechanics , laser , statistics , mathematics
Ultra-bright source of entangled photons is an essential component in optical quantum information processing. Here we propose a counterpropagating path-entangled photon pair sources using a quasi-periodic modulated lithium niobate crystal. The nonlinear crystal designed by a dual-grid method, simultaneously phase-matched two spontaneous parametric down-conversion processes. Signal and idler modes have opposite propagation directions in the two spontaneous parametric down-conversion processes, which is the key to generating path-entangled photon pairs. Compared to copropagating entangled sources, the counterpropagating path-entangled sources result in a much narrower spectrum. The quantum state of the path-entanglement source is not only suited for quantum coding, but also to allow the implementation of complex quantum algorithms on a photonic chip.