Ab initio calculations and ellipsometry measurements of the optical properties of the layered semiconductor In₄Se₃

Authors

L. Makinistian, INTEC-CONICET
E. A. Albanesi, INTEC-CONICET
N. V. Gonzalez Lemus, INTEC-CONICET
A. G. Petukhov, South Dakota School of Mines
D. Schmidt, University of Nebraska-Lincoln
Eva Schubert, University of Nebraska-LincolnFollow
M. Schubert, University of Nebraska-LincolnFollow
Yaroslav B. Losovyj, Louisiana State University at Baton RougeFollow
P. Galiy, Ivan Franko National University of Lviv, 50 Dragomanov Str., 79005 Lviv, Ukraine
Peter A. Dowben, University of Nebraska-LincolnFollow

Date of this Version

2010

Comments

Published in PHYSICAL REVIEW B 81, 075217 (2010). Copyright © 2010 The American Physical Society. Used by permission.

Abstract

In this work, we present a thorough study of the optical properties of the layered orthorhombic compound In₄Se₃. The dielectric function—real and imaginary parts, the complex refraction index, the reflectivity, the absorption coefficient, and the conductivity of In₄Se₃ were calculated with the inclusion of the spin-orbit interaction, using an ab initio FP-LAPW method based on DFT. Also, generalized ellipsometry was employed for more precise measurement of the anisotropic dielectric functions for polarization along crystal a, b, and c axes of orthorhombic absorbing In₄Se₃ single crystals cut approximately parallel to (100) at photon energies from 0.76 to 3.1 eV. Our experimental results show a good agreement with our calculations. We discuss the location and nature of the main optical peaks appearing in the spectra. The obtained optical functions display a rather anisotropic behavior, mainly in the infrared-visible region. Our results seem to be predictive to a high extension, given the scarce experimental information about its optical properties.