PROPERTIES OF STRAINED (IN, GA, AL)AS LASERS WITH LATERALLY MODULATEDACTIVE-REGION

Transmission electron microscopy studies of low indium composition Inx Ga1-xAs insertions (x<0.4) in a GaAs matrix deposited by molecular bea m epitaxy or by metal-organic chemical vapor deposition reveal nanosca le quasiperiodic compositional and morphological modulations. The lumi nescence peak wavelength is found to be a strong function of depositio n parameters and can be tuned from 1.1 to 1.3 mu m for the same x and average thickness of the deposit. Strained (In, Ga Al)As lasers with s uch a laterally modulated InxGa1-xAs active region demonstrate signifi cant depolarization of the electroluminescence. For short cavity lengt h, lasing occurs at energies corresponding to transitions between InxG a1-xAs conduction band and light holelike valence band states. Devices lase at low threshold current densities and demonstrate continuous wa ve operation up to 3 W at room temperature. (C) 1997 American Institut e of Physics.