BURIED-HETEROSTRUCTURE DIODE INJECTION LASER

摘要

BURIED-HETEROSTRUCTURE DIODE INJECTION LASER A buried-heterostructure (BH) diode injection laser capable of operating at low room temperature thresholds and in the lowest order TE, TM or TEM modes. The laser has an elongated groove in a substrate with the groove extending through a pump current confining layer with a central portion of the active layer substantially completely within the groove and substantially completely surrounded by light guiding and carrier confining layers of material having a lower index of refraction than the index of refraction of the material of the active layer. The light guiding and carrier confining layer in contact with the substrate has a central depression within the elongated groove and the central portion of the active layer is bowl-shaped and within the depression such that light waves produced by carrier recombination within the central portion of the active layer when the laser is forward biased are guided in the central portion of the active layer such that the laser produces a light beam having reduced width v. height dimensional variations such that the light beam can be used with symmetrical optical elements such as round lenses.