Triangular-facet laser with optical waveguides grown by selective area metalorganic chemical vapor deposition

A triangular prism-shaped GaAs/AlGaAs laser with rectangular optical waveguides at three corners is proposed and its preliminary lasing characteristics and waveguiding of lasing light are presented. This structure is grown by selective area metalorganic chemical vapor deposition (MOCVD) and consists of a (111)B growth plane and (110) sidewall facets. The advantage of the triangular facet is that the prism growth proceeds while maintaining the equilateral triangle shape even if there is a little fluctuation in the size or shape of the mask and if the layer thickness is increased up to about 1.5 mu m. Lasing at room temperature is observed by optical pumping of low energy (E(th) < 10 pJ). The lasing light can be successfully extracted from the point of the rectangular waveguides. The lasing mode is found to be a ring cavity made of an inscribed equilateral triangle by the longitudinal mode spacing.