Title :
In-line optical phase-sensitive amplifier with pump light source controlled by optical phase-lock loop
Author :
Imajuku, Wataru ; Takada, Atsushi
Author_Institution :
NTT Opt. Network Syst. Labs., Kanagawa, Japan
fDate :
4/1/1999 12:00:00 AM
Abstract :
This paper describes an in-line optical phase-sensitive amplifier (PSA) with a pump laser whose optical phase is locked to that of a randomly modulated signal by using an optical phase-lock loop (OPLL). The OPLL is designed with the capability of optical phase locking at an arbitrary relative phase. Experimental evaluation is presented of the OPLL employing a newly developed external cavity semiconductor ring laser with a spectrum linewidth of less than 20 kHz. Employing this pump laser with the OPLL in conjunction with a 4.4-km long nonlinear fiber Sagnac interferometer (NFSI) yields optical phase-sensitive gain of up to 11 dB. A randomly modulated signal is successfully amplified and confirmed offering a clear eye-opening
Keywords :
fibre optic sensors; laser cavity resonators; light interferometers; light sources; optical communication equipment; optical phase locked loops; optical pumping; ring lasers; semiconductor optical amplifiers; sensitivity; 11 dB; 4.4 km; arbitrary relative phase; clear eye-opening; external cavity semiconductor ring laser; in-line optical phase-sensitive amplifier; nonlinear fiber Sagnac interferometer; optical phase locking; optical phase-lock loop; optical phase-sensitive gain; pump laser; pump light source control; randomly modulated signal; spectrum linewidth; Fiber nonlinear optics; Light sources; Nonlinear optics; Optical amplifiers; Optical interferometry; Optical modulation; Optical pumping; Pump lasers; Semiconductor optical amplifiers; Stimulated emission;
Journal_Title :
Lightwave Technology, Journal of
