Optical constants of layered structured Ga0.75In0.25Se crystals from the ellipsometric measurements


IŞIK M., ÇETİN Ş., Gasanly N., ÖZÇELİK S.

SOLID STATE COMMUNICATIONS, vol.152, no.9, pp.791-793, 2012 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 152 Issue: 9
  • Publication Date: 2012
  • Doi Number: 10.1016/j.ssc.2012.01.043
  • Journal Name: SOLID STATE COMMUNICATIONS
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.791-793
  • Middle East Technical University Affiliated: Yes

Abstract

We have carried out the spectroscopic ellipsometry measurements on Ga0.75In0.25Se single crystals in the 1.2-6.0 eV spectral range at room temperature. The optical constants, real and imaginary parts of the dielectric function, refractive index and extinction coefficient, were found as a result of analysis of ellipsometric data. The critical point analysis of the second derivative spectra of the dielectric function revealed four interband transition structures with critical point energy values of 3.19, 3.53, 4.10 and 4.98 eV. The results of the analysis were compared with those of the ellipsometric studies performed on GaSe which is the main constituent of the Ga0.75In0.25Se crystal. The obtained critical point energies are in good agreement with the energies of the GaSe crystal reported in the literature. (C) 2012 Elsevier Ltd. All rights reserved.