Patent ID: 6560259
Filing Date: 2003-05-06
Classification: B82Y,H01S

Abstract:
A unipolar surface emitting semiconductor laser having a wide lasing region for producing a spatially coherent output beam comprising:a semiconductor resonance cavity for producing a laser mode of diverging counter-propagating traveling wave beams of light derived from unipolar inter-subband transitions within the wide lasing region of the semiconductor laser; a diffraction grating for resonantly coupling the diverging counter-propagating traveling wave beams while also coupling a portion of the traveling wave beams into an output beam transverse to the wide lasing region; and a semiconductor layer for coacting with the traveling wave beams of the resonance cavity and having an effective index of refraction that varies quadratically in a direction transverse to the traveling wave beams of light with the lowest values thereof at centralized portions of the laser and higher values thereof at noncentralized portions of the laser.