A MULTIMODE SELF-CONSISTENT MODEL OF THE LASING CHARACTERISTICS OF BURIED HETEROSTRUCTURE LASERS

Constricted mesa and buried heterostructure lasers have extremely wide modulation bandwidths due to their low parasitic capacitance and resi stance and because the structure provides very high confinement of bot h the carriers and photons in the active layer, The modulation bandwid th of these lasers is limited by current leakage effects and multilate ral mode operation which both conspire to reduce the effective optical gain of the laser for a given operating current, These two problems a re addressed and a fully self-consistent model of the lateral modal be havior and the current leakage problem in buried heterostructure laser s is addressed, The optical problem is solved using a modified version of the weighted index method, which provides a two-dimensional soluti on for optically active material with complex permittivity, and the on set of multimode behavior, where there is a superposition of two or mo re lateral modes, is also examined.