A novel non-uniform two-section DFB semiconductor laser for wavelength tuning

A novel wavelength tunable DFB laser with two non-uniform sections is reported. A 4 nm continuous wavelength tuning range and an 11.1 nm discrete wavelength tuning range were achieved using only one control-current, with SMSR over 30 dB. The structure of the non-uniform two-section single-cavity DFB laser was grown by three-step MOCVD epitaxy and the active layer consists of six undoped 8 nm wide InGaAsP quantum wells.