CONSTANT OUTPUT POWER AND LOW LINEWIDTH IN A SIMPLE WIDE-TUNING DFB LASER WITH MULTIWAVELENGTH CRATING

Step-tuning to widely spaced predefined wavelengths using a single cur rent is demonstrated. A compound distributed-feedback-distributed-Brag g-reflector (DFB-DBR) laser structure including multiwavelength gratin gs (MWG's) on both sections is proposed. MWG's are fabricated bg holog raphic lithography. Each MWG acts as a spectral comb hater. Using vern ier effect between passive and active MWG's, DFB modes are successivel y selected. As wavelength selectivity is performed on the active mediu m without help of facet reflectivity, output power remains the same on all wavelengths. Four 4-nm-spaced DFB modes are accessed with constan t optical output power. Advantages of such a configuration for integra ted components are discussed.