ELECTRON-CAPTURE IN QUANTUM-WELLS VIA SCATTERING BY ELECTRONS, HOLES,AND OPTICAL PHONONS

Electron-capture times due td the electron-electron (e-e), electron-ho le (e-h), and electron-polar optical phonon (e-pop) interactions are c alculated in the GaAs quantum well (QW) with electron and hole densiti es 10(11) cm(-2). The calculated capture times oscillate as a function of the QW width with the same period but with different amplitudes. T he e-h capture time is two to four orders larger and the e-e capture t ime one to three orders larger than the e-pop capture time. The except ions are the QW widths near resonance minima, where the e-e capture ti me is only 2-3 times larger and the e-h capture time 10-100 times larg er. A different physical origin of the oscillatory behavior is demonst rated for the e-e and e-pop capture times. Effects of exchange and deg eneracy on the e-e capture are analyzed. The exchange effect increases the e-e capture time approximately two times while the degeneracy doe s not change the capture time except for the QW depths and widths near the resonance.