Eight-wavelength EDF laser combining tilted fiber grating with sampled fiber grating

Abstract

A new eight-wavelength erbium-doped fiber laser, which utilizes linear cavity structure, was designed and experimentally authenticated. The laser was composed of two Sagnac loops: a left loop containing a fiber coupler (FC) with power ratio of 50:50 and a tilted fiber grating (TFG), and a right loop consisting of another FC, a sampled fiber grating (SFG) and three-ring-type polarization controller (PC). The TFG had many inhomogeneous peaks with maximum power differences of 3 dB and maximum modulation depths of 16 dB. Two adjacent transmission peaks in the SFG had approximately 0.3 nm spacings and maximum modulation depths of 8 dB. The two loops with TFG and SFG were jointly utilized to motivate multi-wavelength. When the PC was tuned to cause the PHB effect, 21 sorts of diverse lasing lines were achieved. All lasing lines with the OSNRs of more than 20 dB had fewer than 0.21 nm line widths.