Bistable Operation of 1-D Photonic Crystal Laser With Saturable Absorber

Bistable operation of a 1-D photonic crystal (PC) laser with a nonlinear absorber is presented. The model is based on a modified transfer matrix method with a Bloch wave formalism and allows to define, in an easy way, the influence of the real structures parameters, such as a period of the structure, contrast of the refractive indices of crystal layers, the number of the primitive cells creating the PC, the loss level, and the pumping level on the bistable operation of the investigated structures. The geometry of the PC primitive cell (i.e., a period of the PC structure and the number of the primitive cells creating the PC) is chosen in such a way as to obtain the laser wavelength at the bandgap edge where considerable enhancement of the laser gain is observed. Furthermore, four laser structures, in which the absorber is located at different positions relating to the active medium in the resonator, are examined. The influences of the PC geometry, the output mirror reflectivity, and the saturable losses on the hysteresis loop are investigated.