Ms. Kushwaha et B. Djafarirouhani, A GREEN-FUNCTION THEORY OF PLASMONS IN 2-DIMENSIONAL SEMICONDUCTOR STRUCTURES - FINITE MAGNETIC-FIELD, Annals of physics, 265(1), 1998, pp. 1-51
A theoretical investigation has been made of the magnetoplasmon excita
tions in several two-dimensional (2D) semiconductor structures subject
ed to an applied magnetic field in the framework of a Green-function (
or response function) theory. The applied magnetic field Bo is assumed
to be oriented parallel to the interfaces and perpendicular to the di
rection of propagation (Voigt geometry). The material layers are chara
cterized by frequency-dependent dielectric function and the quantum-si
ze effects are ignored. The Green-function theory generalized to be ap
plicable to the 2D systems enables us to derive explicit expressions f
or the corresponding response functions (associated with the electroma
gnetic fields) which can in turn be used to calculate almost all physi
cal properties of the system at hand. A simple analytical diagnosis of
the general results for all the systems investigated here leads us to
reproduce exactly the previously well-established results, for the di
spersion relations for plasmons and magnetoplasmons. obtained within a
different theoretical framework. As examples, we have incorporated nu
merical results on the dispersion characteristics of magnetoplasmons i
n several geometries. It is found that the excitation spectrum in the
Voigt geometry contains a complete magnetic-field-dependent gap within
which no magnetoplasmons are allowed to propagate. The simplicity and
the compact forms of the desired results give the present theory a wi
dth of interest. The implications of the analytical and numerical resu
lts have been discussed briefly. (C) 1998 Academic Press.