ELECTRON - INTERFACE-PHONON SCATTERING IN GRADED QUANTUM-WELLS OF GA1-XALXAS

Using the method of series expansion, interface-phonon vibrational mod es are calculated in the dielectric continuum model for the graded qua ntum well of Ga1-xAlxAs with a Ga0.6Al0.4As barrier. The intrasubband and intersubband scattering rates are obtained as functions of quantum -well width. The results reveal that the behavior of interface phonon modes is very different from that in a square quantum-well structure. It is found that the electron-interface-phonon scattering rates can be changed remarkably in a graded quantum-well structure compared with t hose in a square quantum-well structure, which is useful for some devi ce applications.