G. Slavcheva et I. Yanchev, PATH-INTEGRAL APPROACH IN THE CALCULATION OF THE ELECTRON-DENSITY OF STATES AT THE SEMICONDUCTOR-INSULATOR INTERFACE, Philosophical magazine. B. Physics of condensed matter. Statistical mechanics, electronic, optical and magnetic, 74(6), 1996, pp. 715-732
The electron density of states near the semiconductor-insulator interf
ace is calculated using the Feynman's path-integral method. Statistica
l interface charge distribution properties have been taken into accoun
t and the Fourier transform of the binary correlation function of the
random potential has been computed. Finally the electron density of st
ates in the band tail in a first cumulant approximation is obtained. T
he exponential dependence of the density of states on the energy is si
milar to that obtained for the three-dimensional screened Coulomb pote
ntial at a limit of weak screening. The exponent b(v) of the density o
f states is the same and the pre-exponential factor a(v) are approxima
tely two orders of magnitude smaller than those obtained using the scr
eened Coulomb model random potential. Some numerical results have been
presented for the system Si-SiO2.