Narrow line width dual wavelength EDFA based random fiber laser

Abstract

In this work, we present a tunable single longitudinal-mode (SLM) dual wavelength fiber laser structure of 14 nm separation of wavelengths. The laser action is contingent on Rayleigh backscattering phenomenon in a single mode fiber (SMF 28e) of 1 km length acting as a distributed mirror, and an Erbium Doped Fiber amplifier (EDFA) for optical amplification. Two optical filters are used as wavelength selectors. Two Faraday Rotator mirrors are used to stabilize the two lasing wavelengths against fiber random birefringence. The optical signal to noise ratio (OSNR) is 44 dB. The linewidths of our laser are 2.6 and 2.7 kHz at 1550 and 1564 nm respectively, at a pump power of 150 mW.