ELECTRON-MOBILITY AND TERAHERTZ ABSORPTION DUE TO INTERACTIONS WITH CONFINED ACOUSTIC PHONONS IN A FREESTANDING QUANTUM-WELL

Electron transport and optical parameters of a free-standing quantum w ell are studied theoretically. Electron interactions with photons and confined acoustic phonons through the deformation potential are treate d rigorously. The quantum kinetic equation for the electron distributi on function is solved numerically for nondegenerate as well as degener ate electron gases and the electron momentum relaxation time, the elec tron mobility and the absorption coefficient in terahertz range are ob tained. Both the electron transport and optical parameters exhibit pec uliarities, related to the confined acoustic phonon spectrum. They are displayed as peaks at the electron momentum relaxation time dependenc e on energy and at the second derivative of the absorption coefficient over photon energy. The positions of the peaks is associated with the energies of confined acoustic phonons.