Title :
Cross-Gain Modulation Suppression in a Raman-Assisted Fiber Optical Parametric Amplifier
Author :
Xiaojie Guo ; Shu, Chester
Author_Institution :
Dept. of Electron. Eng., Chinese Univ. of Hong Kong, Hong Kong, China
Abstract :
We propose to use a backward Raman pump to suppress cross-gain modulation (XGM) during multiwavelength amplification in a fiber optical parametric amplifier (FOPA). The performances of two-wavelength amplification have been experimentally compared between FOPAs with and without the Raman pump under the condition of identical unsaturated gains. With Raman-assisted amplification, a larger range of input signal power is supported without causing significant depletion of the parametric pump. Consequently, the XGM crosstalk is effectively suppressed. The improvement is explained by compensation of the parametric pump power through the Raman gain. In our experiment, a 6.3-dB improvement has been obtained in the receiver sensitivity of a 10-Gb/s return-to-zero ON/OFF keying signal at the 10-8 bit-error rate level under simultaneous amplification of two data streams. The error floor has also been removed.
Keywords :
Raman spectra; error statistics; optical crosstalk; optical fibre amplifiers; optical modulation; optical parametric amplifiers; optical receivers; Raman-assisted fiber optical parametric amplifier; XGM crosstalk suppression; backward Raman pump; bit-error rate level; cross-gain modulation suppression; gain 6.3 dB; multiwavelength amplification; optical receiver sensitivity; return-to-zero ON-OFF keying signal; Gain; Nonlinear optics; Optical amplifiers; Optical fiber amplifiers; Stimulated emission; Cross gain modulation; Raman scattering; fiber optical parametric amplifier; nonlinear fiber optics;
Journal_Title :
Photonics Technology Letters, IEEE
DOI :
10.1109/LPT.2014.2324566