Emission characteristics of AlGaAs/GaAs laser heterostructures grown from nonstoichiometric melts

Various heterostructures for laser diodes are examined, and it is shown that, for best results, heterostructures should be grown from a thin (about 0.05 cm) layer of nonstoichiometric melt at low cooling rates. It is also shown that the threshold lasing current density does not depend on the alloying element (Sn or Tn for n-emitters and Zn and Ge for p-emitters) and depends only slightly on the emitter thickness. The addition of aluminum to GaAs shifts the emission wavelength to 670-690 nm for cooled lasers and to 750 nm for room-temperature lasers. CW emitting powers of 220 mW and 65 mW have been achieved with cooled diodes and room-temperature lasers, respectively.