Narrow Line-width Single Mode Optical Random Fiber Laser

Abstract

In this chapter we have demonstrated a novel tunable separation of dual-wavelength random fiber laser. Two configurations are implemented with two different gain media, SOA and EDFA. The two configurations have demonstrated a tuning dual-wavelength separation. The line-widths of each dual mode are measured using Self-Delayed-Heterodyne method and demonstrated a SLM operation in all the tuning range with line-widths range 3 – 11.5 kHz, for the SOA based configuration, and 2.6 kHz for the EDFA based configuration. The impact of increasing the pump current for SOA, and pump power for EDFA on the line-width variation is also investigated. The results indicate minor increase in line-width of each mode with increasing the pump current or power. The optical peak power and peak wavelength stability are characterized at five different separations between the dual wavelengths in SOA-based random fiber lasersand showed acceptable fluctuations, which opens the door to use this dual-wavelength laser in Terahertz generation.