Experimental demonstration of DFB semiconductor lasers with varying longitudinal parameters

The distributed-coupling-coefficient and distributed-coupling-coefficient corrugation-pitch-modulated DFB lasers are experimentally demonstrated. The proposed lasers maintain good side mode suppression ratio over 50dBfrom 2.5 times to 12.5 times threshold current. The grating profiles of varying longitudinal parameters are equivalently obtained by specially designed sampled Bragg gratings and fabricated by conventional holographic exposure and μm-level photolithography.