EMISSION-SPECTRA AND MODE STRUCTURE OF INAS GAAS SELF-ORGANIZED QUANTUM-DOT LASERS/

A study of the emission spectra and mode structure of InAs/GaAs self-o rganized quantum dot lasers is presented. In contrast to conventional bulk or quantum well lasers, the number of lasing modes increases abov e threshold. This behavior is shown to be consistent with carriers loc alized in noninteracting dots and a resultant inhomogeneously broadene d gain spectrum. The lasing spectra are found to have a complicated fo rm with groups of longitudinal modes separated by nonlasing spectral r egions and lasing occurring via a number of different lateral modes. T hese characteristics are discussed in terms of the spatially discrete nature of the quantum dots. (C) 1998 American Institute of Physics.