TIGHT-BINDING APPROACH TO RESONANT TUNNELING WITH ELECTRON-PHONON COUPLING

We consider resonant tunneling through a double barrier when the electrons interact with longitudinal-optical phonons in the double-barrier well. We use a tight-binding model for the electron Hamiltonian, with a linear coupling to the phonon modes. Phonon-mediated scattering amplitudes for the double-barrier structure are efficiently obtained by a recursive Green-function technique. This technique allows us to go beyond the unrealistic assumption of Lorentzian line shapes, used in previous treatments. Our results are in qualitative agreement with earlier calculations, but quantitatively the phonon peaks are enhanced typically by 50%.