Tunable wavelength optical injection locked actively Q-switched random fiber laser based on RPS-FBG and EOM and analysis of multi pulse phenomenon

Abstract

In this paper, a tunable wavelength optical injection locked actively Q-switched random fiber laser based on random phase-shifted fiber Bragg grating (RPS-FBG) and electro-optic modulator (EOM) is proposed and experimentally verified. In the experiment, wavelength locking is achieved by injecting an external seed light from a wavelength tunable laser into the resonant cavity, resulting in a stable single-wavelength laser with a wavelength tuning range of approximately 37.4 nm. In the injection locked state, the wavelength drift of the laser is less than 0.04 nm and the power fluctuation is less than 0.14 dB within 1 h, which has good stability. An EOM is added to introduce actively Q-switched. When the pump power increases from 50mW to 350mW, single pulse to three pulses can be generated. The proposed multi-pulse injection-locked random fiber laser is of great significance for the research of wavelength selection and pulse coding in disordered systems.