A widely tunable erbium-doped fiber laser using closed loop control

We propose and experimentally demonstrate a novel single- frequency erbium-doped fiber ring laser which features remarkable wavelength stability with the use of closed loop control. The system consists of a tunable FBG filter, erbium-doped fiber and a wavelength detector which detects the input wavelength to activate the closed loop control system to stabilize the output wavelength. The stability of the laser is investigated, the optimum operation wavelength range (1530- 1570 nm) for the laser to achieve output power of 1.3 dBm, power variation of less than 0.2 dB and SMSR of up to 61.2 dB (0.02nm resolution) is demonstrated.