Blue-green buried-ridge laser diodes

Summary form only given. An attempt is being made to develop short wavelength (green and blue) laser diodes with performance suitable for use in optical data storage systems. Buried-ridge laser diodes operating in the blue-green (λ=511 nm) are reported. The starting material is a separate-confinement heterostructure consisting of a strained, pseudomorphic CdZnSe quantum well, ZnSSe light-guiding layers, and MgZnSSe cladding layers. The II-VI layers are grown by MBE (molecular beam epitaxy) and are nominally lattice-matched to the GaAs substrate. Ridges, typically 2 or 3 μm wide, are formed using ion beam etching, and are subsequently buried with ZnS in a self-aligned process that results in a planar surface. Laser diodes with room-temperature pulsed threshold currents of 2.5 mA have been obtained. Single lateral model operation is indicated by the far-field pattern of these devices