WIGNER FUNCTION FOR OPEN SYSTEMS WITH ELECTRON-PHONON INTERACTION

The Wigner-function (WF) formalism is used to analyze the quantum dyna mics of charge carriers in presence of electron-phonon (e-p) interacti on in open mesoscopic systems making use of the perturbation theory wi th the external fields incorporated into the unperturbed Hamiltonian. Proper boundary conditions have been chosen and the transport phenomen on inside the device is treated in such a way that boundary conditions at finite positions are kept unaltered, even though the basis of exte nded scattering states is used.