Far Infrared Investigation of Plasmon-LO Phonon Coupling and Surface Polaritons Modes in Donor Doped Cd1-xHgxTe and CdTe Thin Layer on GaAs Substrate
Authors: Shayesteh, S.F.; Zadeh, J.H.
Source: International Journal of Infrared and Millimeter Waves, Volume 23, Number 10, October 2002 , pp. 1465-1474(10)
Abstract:Infrared Fourier transform spectroscopy has been used to investigate phonon and plasmon modes in Cd1-xHgxTe and CdTe thin layer on GaAs substrate. Attenuated total reflection (ATR) spectroscopy has been used to excite surface plasmon and phonon polaritons. The plasmon-LO phonon coupling modes in samples are studied by dispersion curve calculation for various carrier concentrations. There exist three branches of coupled modes in dispersion curve. For analysis of the far infrared polarized reflectivity spectra we employ the harmonic oscillator dielectiic function model and the Drude model for free carrier response. We find that the coupling modes dependent to the concentration of free carriers. Furthermore, the experimental data have been used to calculate carrier concentration, composition parameter, mobility of carrier, thickness of layer and gap energy.
Document Type: Research Article
Affiliations: Department of Physics, University of Guilan, P.O. Box 1914, Rasht, Iran
Publication date: October 1, 2002