DESIGN PROPOSAL OF AN ASYMMETRIC 3-PHASE-SHIFT DISTRIBUTED-FEEDBACK LASER-DIODE

The effects of using asymmetric phase shifts along the corrugation of a three-phase-shift (3PS) distributed feedback (DFB) laser diode (LD) have been investigated. Based on the transfer matrix method (TMM), des ign contours showing variations of the threshold gain margin DELTAalph a and the internal field uniformity F are presented with respect to th e phase-shift values and the phase-shift positions (PSP). It has been found that in order to minimize the effects of spatial hole burning (S HB) and hence maintain a stable single longitudinal mode (SLM) oscilla tion, the following criteria should be used: (i) center phase shift, t heta3 = pi/6, (ii) 0.15 < PSP < 0.35, and (iii) 2 pi/9 < theta(i) (i = 2, 4) < 4 pi/9. (C) 1994 John Wiley & Sons, Inc.