Original scientific paper
Green's function method in the theory of electron - phonon interaction
N. Hasić
; University of Sarajevo, Sarajevo
Abstract
The effect of electron-phonon interaction on electron motion has been calculated with the Green's function method. It is assumed that the whole system is composed of electrons with screened Coulomb interaction and of longitudi nal phonons with an energy tSq, where S is the velocity of sound. This effect has been calculated to the second powers in the interaction of the self energy part of electrons. A method is developed which enables one to consider the convenient application of Green's functions to the problem. The calculation . of Fourier transform of the Green's function G (k, i) has been carried out by using the ordinary perturbation method where annihilation operator is expanded in power series of time. Agreement is shown with a theory that uses Wick's theorem. Such an application of the perturbation method enables us to avoid the adiabatic hypothesis.
Keywords
Hrčak ID:
320121
URI
Publication date:
23.11.1969.
Visits: 0 *