Title :
Analysis of TE/TM mode selectivity in DFB lasers with a phase-shift region
Author :
Kinoshita, Jun-Ichi
Author_Institution :
Toshiba Corp., Yokohama, Japan
Abstract :
In phase-shift distributed feedback (DFB) lasers, there is limited suppression of the TM mode despite extremely large submode suppressibility. The TE/TM mode selectivity of a DFB laser structure with a nonuniform waveguide region as the phase shifter is analyzed. Calculations of the threshold gain difference between the TE and TM modes are performed using the effective index method and the coupled-wave theory. It is found that the TM mode suppressibility can be doubled by optimizing the dimensions of the phase-shift region. This structure overcomes the TM mode problem.<>
Keywords :
distributed feedback lasers; laser modes; DFB lasers; TE mode; TM mode; coupled-wave theory; distributed feedback lasers; mode selectivity; phase shifter; submode suppressibility; Distributed feedback devices; Indium phosphide; Laser feedback; Laser modes; Laser theory; Optical waveguides; Performance gain; Phase shifters; Waveguide lasers;
Journal_Title :
Photonics Technology Letters, IEEE
