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Title: Thickness-dependent dispersion parameters, energy gap and nonlinear refractive index of ZnSe thin films

Abstract

Highlights: • Combined experimental and theoretical researches on ZnSe Thin Films. • The film thickness and refractive index were determined using envelope method. • The absorption coefficient and the energy gap were calculated. • Dispersion parameters were determined using Wemple-DiDomenico relation. • The third order susceptibility and nonlinear refractive index were calculated. - Abstract: Zinc selenide (ZnSe) thin films with different thicknesses were evaporated onto glass substrates using the thermal evaporation technique. X-ray diffraction analysis confirmed that both the film and powder have cubic zinc-blende structure. The fundamental optical parameters like absorption coefficient, extinction coefficient and band gap were evaluated in transparent region of transmittance and reflectance spectrum. The optical transition of the films was found to be allowed, where the energy gap increased from 2.576 to 2.702 eV with increasing film thickness. Also, the refractive index value increase with increasing film thickness. The refractive indices evaluated through envelope method were extrapolated by Cauchy dispersion relationship over the whole spectra range. Additionally, the dispersion of refractive index was determined in terms of Wemple-DiDomenico single oscillator model. Third order susceptibility and nonlinear refractive index were determined for different thickness of ZnSe thin films.

Authors:
 [1];  [2];  [3];  [4];  [5];  [6]
  1. School of Computer Science & Engineering, Faculty of Engineering, SMVD University, Kakryal, Katra 182320, J&K (India)
  2. Physics Department, Faculty of Science, Al-Azhar University, Assiut 71542 (Egypt)
  3. Department of Physics, Faculty of Science, Al-Azahar University, Cairo (Egypt)
  4. Physics Department, Faculty of Science, Sohag University, 82524 Sohag (Egypt)
  5. Physics Department, Faculty of Science, Assiut University, Assiut 71516 (Egypt)
  6. Material Science Research Laboratory, Department of Physics, S. V. College, Aligarh 202001, U.P. (India)
Publication Date:
OSTI Identifier:
22581591
Resource Type:
Journal Article
Resource Relation:
Journal Name: Materials Research Bulletin; Journal Volume: 80; Other Information: Copyright (c) 2016 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; ABSORPTION; ABSORPTION SPECTRA; CUBIC LATTICES; ENERGY GAP; EVAPORATION; MICROSTRUCTURE; OSCILLATORS; POWDERS; REFRACTIVE INDEX; SEMICONDUCTOR MATERIALS; SUBSTRATES; THICKNESS; THIN FILMS; X-RAY DIFFRACTION; ZINC SELENIDES; ZINC SULFIDES

Citation Formats

Prakash, Deo, Shaaban, E.R., E-mail: esam_ramadan2008@yahoo.com, Shapaan, M., Mohamed, S.H., Othman, A.A., and Verma, K.D., E-mail: kdverma1215868@gmail.com. Thickness-dependent dispersion parameters, energy gap and nonlinear refractive index of ZnSe thin films. United States: N. p., 2016. Web. doi:10.1016/J.MATERRESBULL.2016.03.039.
Prakash, Deo, Shaaban, E.R., E-mail: esam_ramadan2008@yahoo.com, Shapaan, M., Mohamed, S.H., Othman, A.A., & Verma, K.D., E-mail: kdverma1215868@gmail.com. Thickness-dependent dispersion parameters, energy gap and nonlinear refractive index of ZnSe thin films. United States. doi:10.1016/J.MATERRESBULL.2016.03.039.
Prakash, Deo, Shaaban, E.R., E-mail: esam_ramadan2008@yahoo.com, Shapaan, M., Mohamed, S.H., Othman, A.A., and Verma, K.D., E-mail: kdverma1215868@gmail.com. 2016. "Thickness-dependent dispersion parameters, energy gap and nonlinear refractive index of ZnSe thin films". United States. doi:10.1016/J.MATERRESBULL.2016.03.039.
@article{osti_22581591,
title = {Thickness-dependent dispersion parameters, energy gap and nonlinear refractive index of ZnSe thin films},
author = {Prakash, Deo and Shaaban, E.R., E-mail: esam_ramadan2008@yahoo.com and Shapaan, M. and Mohamed, S.H. and Othman, A.A. and Verma, K.D., E-mail: kdverma1215868@gmail.com},
abstractNote = {Highlights: • Combined experimental and theoretical researches on ZnSe Thin Films. • The film thickness and refractive index were determined using envelope method. • The absorption coefficient and the energy gap were calculated. • Dispersion parameters were determined using Wemple-DiDomenico relation. • The third order susceptibility and nonlinear refractive index were calculated. - Abstract: Zinc selenide (ZnSe) thin films with different thicknesses were evaporated onto glass substrates using the thermal evaporation technique. X-ray diffraction analysis confirmed that both the film and powder have cubic zinc-blende structure. The fundamental optical parameters like absorption coefficient, extinction coefficient and band gap were evaluated in transparent region of transmittance and reflectance spectrum. The optical transition of the films was found to be allowed, where the energy gap increased from 2.576 to 2.702 eV with increasing film thickness. Also, the refractive index value increase with increasing film thickness. The refractive indices evaluated through envelope method were extrapolated by Cauchy dispersion relationship over the whole spectra range. Additionally, the dispersion of refractive index was determined in terms of Wemple-DiDomenico single oscillator model. Third order susceptibility and nonlinear refractive index were determined for different thickness of ZnSe thin films.},
doi = {10.1016/J.MATERRESBULL.2016.03.039},
journal = {Materials Research Bulletin},
number = ,
volume = 80,
place = {United States},
year = 2016,
month = 8
}
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