CONTROL OF LASING WAVELENGTH IN DISTRIBUTED-FEEDBACK LASERS BY ANGLING THE ACTIVE STRIPE WITH RESPECT TO THE GRATING

We proposed and demonstrated a new and very simple technique of varyin g the lasing wavelength of distributed feedback (DFB) lasers with the need for fabricating gratings with different pitches. This is accompli shed by angling the active stripe at an oblique angle with respect to the axis of the grating lines. This technique should be particularly s uitable for fine tuning of lasing wavelength, and it eases the stringe nt demand on precise control of absolute grating pitches. It should be useful and important for dense (wavelength division multiplexing (WDM ) applications and monolithic integration of multiwavelength DFB laser s.