Combination index/gain guided semiconductor lasers

In a semiconductor laser comprising a plurality of contiguous semiconductor layers deposited on a substrate, one or more of said layers forming an active region, said active region permitting carrier recombination and light generation in at least one portion thereof and supporting radiation propagatingunder lasing conditions in an optical cavity established between end facets of the laser, said active region characterized by having in combination at least one index guiding region and at least one gain guiding region integrally coupled to one another relative within said optical cavity.