Bare LO-Phonon Peak in THz-Emission Signals: a Dielectric-Function Analysis
arXiv:cond-mat/0210049 · doi:10.1590/S0103-97332002000200048
Abstract
We present a normal-mode analysis of coupled photocarrier-phonon dynamics in Te. We consider a dielectric function which accounts for LO phonons and the electron-hole gas within the Debye-Huckel model and RPA. Our main finding is the existence of a bare LO phonon mode in the system even at high carrier density. This oscillation is an unscreened L- mode arising from ineffective screening at large wave vectors. This mode is consistent with the bare LO-phonon peak in recent THz-emission spectra of Te.
3 pages, 1 figure, Special Issue: Proceedings of the 10th Brazilian Workshop on Semiconductor Physics, Guaruja/SP, April/2001