RESONANT-TUNNELING THROUGH A COUPLED DOUBLE-QUANTUM-WELL IN THE PRESENCE OF ELECTRON-PHONON INTERACTION

A coupled double-quantum-well resonant tunneling structure in the pres ence of electron-phonon interaction is investigated carefully using th e nonequilibrium Green's functions method. The tunneling current formu la through this system under a de voltage has been derived. Two specia l cases are considered which show how LO phonon-emission-assisted and LO phonon-absorption-assisted tunneling come into effect. In some case s, the LO phonon-emission-assisted tunneling is suppressed due to the Pauli exclusion principle, while the LO phonon-absorption-assisted tun neling is much more prominent when elastic resonant tunneling is impos sible.