Phase-locked semiconductor laser device

摘要

A phase-locked semiconductor laser device comprising a laminated structure in which a plurality of first semiconductor layers having the substantially same composition are stacked in a manner to be sandwiched between second semiconductor layers having a band gap wider, and a refractive index lower, than those of said first semiconductor layers; a third semiconductor layer which is disposed in contact with at least one of side faces of said laminated structure parallel to a traveling direction of a laser beam, which is not narrower in the band gap and not higher in the refractive index than said first semiconductor layers and which does not have the same conductivity type as, at least, that of said first semiconductor layers; means to inject current into an interface between said first semiconductor layers and said third semiconductor layer disposed on the side face of said laminated structure; and means to act as an optical resonator for the laser beam.