Title :
Spatial dispersion effects in the exciton-polariton reflectivity spectra of CuGaS2 crystals
Author :
Syrbu, N. ; Ursaki, Veaceslav ; Nyari, T. ; Blaje, M. ; Prunic, P. ; Tezlevan, V.
Author_Institution :
Tech. Univ. of Moldova, Kishinau, Moldova
Abstract :
The analysis of the exciton reflectivity contour in CuGaS2 crystals at 8 K was carried out. Absorption and luminescence spectroscopy was employed for additional characterization. The value of the exciton Ridberg constant ℜ=0.03247 eV, the energy of the continuum Egn+∞=2.50305 eV and the thickness of the exciton-free layer L=22 Å were deduced from this analysis. The excited n=2 (2.53323 eV) and n=3 (2.53774 eV) states of the excitons were determined. The upper polariton branch was drawn from the angular dependence of the reflectivity
Keywords :
copper compounds; excitons; gallium compounds; infrared spectra; optical dispersion; photoluminescence; polaritons; reflectivity; ternary semiconductors; 2.50305 eV; 2.53323 eV; 2.53774 eV; 22 angstrom; 8 K; CuGaS2; angular dependence; continuum energy; exciton Ridberg constant; exciton-free layer; exciton-polariton reflectivity spectra; luminescence spectroscopy; spatial dispersion effects; upper polariton branch; Absorption; Crystalline materials; Crystals; Dispersion; Excitons; Luminescence; Nonlinear optics; Reflectivity; Spectroscopy; Stimulated emission;
Conference_Titel :
Semiconductor Conference, 2000. CAS 2000 Proceedings. International
Conference_Location :
Sinaia
Print_ISBN :
0-7803-5885-6
DOI :
10.1109/SMICND.2000.890196
