Canadian Journal of Physics

Externally stimulated excitonic system

Rajka P. Djajić-Jovanović, D. M. Ćirić, Momir Marinković, Bratislav S. Tosic

Published Feb 1, 1987• 2 citations

Abstract

The behaviour of the excitonic system stimulated by an external microscopic electric field is analyzed. The mathematical analysis is applied using the Green function of the type [Formula: see text]. This opens the possibility of strictly applying Wick's theorem for the decoupling. The pairing of operators is performed for the same, as well as for different, moments of time. Using the Green function calculated in this way, we derive the dielectric constant and the refraction and absorption indices. It is shown that the presense of external stimulation shifts the principal absorption and refraction peaks towards higher frequencies, making them, at the same time, less prominent. Thus, the conclusion is that external stimulation cannot be used to construct better absorbers of the light energy although external stimulation is able to increase absorption as well as the refraction at frequencies higher than the resonant one.

DOI: 10.1139/p87-025

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