A novel distributed feedback fiber laser based on equivalent phase shift

A distributed feedback fiber laser employing an equivalent phase shift (EPS) of /spl pi/ is studied theoretically and experimentally for the first time. The EPS is formed through extending one sampling period by 50% in the center of a sampled Bragg grating. An output power of 0.20 mW with sidemode suppression of 67 dB is experimentally observed.