Eur. Phys. J. B 20, 27-33 (2001)
https://doi.org/10.1007/PL00011092

Sum rule for the optical absorption of an interacting many-polaron gas

Departement Natuurkunde, Universiteit Antwerpen - UIA, Universiteitsplein 1, B2610 Antwerpen, Belgium

Corresponding author: ^a devreese@uia.ua.ac.be

Received: 26 April 2000
Revised: 5 December 2000
Published online: 15 March 2001

Abstract

A sum rule for the first frequency moment of the optical absorption of a many-polaron system is derived, taking into account many-body effects in the system of constituent charge carriers of the many-polaron system. In our expression for the sum rule, the electron-phonon coupling and the many-body effects in the electron (or hole) system formally decouple, so that the many-body effects can be treated to the desired level of approximation by the choice of the dynamical structure factor of the electron (hole) gas. We calculate correction factors to take into account both low and high experimental cutoff frequencies.