Pump suppressed four-wave mixing in optical fibers for correlated photon generation using feedback technique

Authors:
Publisher website
Google Scholar
Abstract
In this paper we propose and demonstrate a novel technique to suppress pump in four-wave mixing experiments. The residual pump powers at the fiber output are reflected by fiber-Bragg gratings (FBGs), amplified by an EDFA to compensate for pump losses in feedback path, and fed back to the fiber. With the increase in total input power to the fiber, the ratio of signal and idler to pump increases. Additional optical filters can then be used for further pump suppression. In our experiments, two pump waves of wavelengths 1549.70nm and 1549.85nm are combined using a 3dB coupler and fed to a highly-nonlinear fiber (HNLF) of length 1km, nonlinear coefficient of 12.4/W-km, and zero dispersion wavelength (ZDW) of 1513nm. Without feedback, we obtained the signal and idler to pump ratios of -21dB and -20.6dB respectively. After filtering by FBGs of 95% reflectivity and unity gain feedback, the ratio becomes - 14.1dB and -12.2dB respectively. When the residual pumps are amplified and fed back to the HNLF, the ratio improves to -7.5dB and -8.6dB indicating the potential of our method.

This publication has 8 references indexed in Scilit: