Role of Absorption on the Generation of Quantum-Correlated Photon Pairs Through FWM
Silva, N. A.
Pinto, A. N.
IEEE Journal of Quantum Electronics Vol. 48, Nº 11, pp. 1380 - 1388, November, 2012.
ISSN (print): 0018-9197
Scimago Journal Ranking: 1,37 (in 2012)
Digital Object Identifier: 10.1109/JQE.2012.2213802
The impact of fiber absorption on the generation rate of quantum-correlated photon pairs through spontaneous four-wave mixing (FWM) in optical fibers is studied theoretically. We quantify the impact of the loss through the analysis of the Cauchy-Schwarz correlation parameter and the Clauser, Horne, Shimony, and Holt (CHSH) inequality. Results show that fiber loss can improve the quantum-correlation between the photon pairs. This is a consequence of the decrease of the individual signal and idler photon-fluxes, which reduces the rate of uncorrelated photons generated through Raman scattering inside the optical fiber. Findings show that a high degree of polarization entanglement is obtained when the ratio of signal to idler photon-fluxes lies between 0.5 and 0.8, in a regime with high losses on the signal wave.