ELECTRON-CAPTURE IN GAAS QUANTUM-WELLS VIA ELECTRON-ELECTRON AND OPTIC PHONON-SCATTERING

Electron capture times in a quantum well (QW) structure with finite el ectron density are calculated for electron-electron (e-e) and electron -polar optic phonon (e-pop) scattering. We find that the capture time oscillates as function of the QW width for both processes with the sam e period, but with very different amplitudes. For an electron density of 10(11) cm(-2) the e-e capture time is 10(1) - 10(3) times larger th an the e-pop capture time except for QW widths near the resonance mini ma, where it is only 2-3 times larger. With increasing density the e-e capture time decreases and near the resonance becomes smaller than th e e-pop capture time. Our e-e capture times are three orders larger th an the results of Blom et al. [Appl. Phys. Lett. 62, 1490 (1993)]. The role of the e-e capture in QW lasers is therefore readdressed. (C) 19 96 American Institute of Physics.