OPTICAL POWER COUPLING IN SYMMETRIC TRIANGULAR PERIODIC STRUCTURES

SEM picture of rectangular gratings realised by chemical etching mostly resembled a triangular grating. Symmetric triangular gratings can give better directionality to the DFB laser beam. In this communication,the optimal Bragg order,grating period and tooth height,active layer thickness were presented from a study of the optical power coupling for a symmetric triangular GaAs‐AlGaAs structure. The numerical parameters so obtained were compared to the reported results and found that chemically etched rectangular grating obeys the theory of symmetric triangular grating with remarkable accuracy.