BOUND-STATES OF COUPLED PLASMON-PHONON MODES AT NEUTRAL DONORS IN SEMICONDUCTOR QUANTUM-WELLS

The bound states of plasmons, of phonons and of coupled plasmon-phonon modes at neutral donors in semiconductor quantum well systems have be en studied here. The interaction of plasmon-phonon excitations, which are important in compound semiconductor systems, with electrons, and t he coupling of plasmons with electrons have been derived in the long w ave length limit of the Random Phase approximation. These interactions are used to derive expressions for the binding energies of the collec tive excitations to neutral donors. The dependence of the binding ener gy of the coupled plasmon-phonon modes on the well width of quantum we lls is found to be particularly rich. The present results are in gener ally good accord with available experimental data for quantum well sys tems.