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Title: Local versus global electronic properties of chalcopyrite alloys: X-ray absorption spectroscopy and ab initio calculations

Abstract

Element-specific unoccupied electronic states of Cu(In, Ga)S{sub 2} were studied as a function of the In/Ga ratio by combining X-ray absorption spectroscopy with density functional theory calculations. The S absorption edge shifts with changing In/Ga ratio as expected from the variation of the band gap. In contrast, the cation edge positions are largely independent of composition despite the changing band gap. This unexpected behavior is well reproduced by our calculations and originates from the dependence of the electronic states on the local atomic environment. The changing band gap arises from a changing spatial average of these localized states with changing alloy composition.

Authors:
;  [1];  [2];  [3];  [4];  [5];  [6]
  1. Institut Lumière Matière and ETSF, UMR5306 Université Lyon 1-CNRS, Université de Lyon, F-69622 Villeurbanne Cedex (France)
  2. Institut für Festkörperphysik, Friedrich-Schiller-Universität Jena, Max-Wien-Platz 1, 07743 Jena (Germany)
  3. Helmholtz-Zentrum Berlin für Materialien und Energie, Hahn-Meitner Platz 1, 14109 Berlin (Germany)
  4. Nano-Bio Spectroscopy Group and ETSF Scientific Development Centre, Departamento de Física de Materiales, Centro de Física de Materiales CSIC-MPC and DIPC, Universidad del País Vasco UPV/EHU, Avenida de Tolosa 72, E-20018 San Sebastián (Spain)
  5. (Germany)
  6. Fritz Haber Institute, Max Planck Society, Faradayweg 4-6, 14195 Berlin (Germany)
Publication Date:
OSTI Identifier:
22314387
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 116; Journal Issue: 9; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; ABSORPTION; ABSORPTION SPECTROSCOPY; ALLOYS; CATIONS; CHALCOPYRITE; DENSITY FUNCTIONAL METHOD; X-RAY SPECTROSCOPY

Citation Formats

Sarmiento-Pérez, Rafael, Botti, Silvana, E-mail: silvana.botti@univ-lyon1.fr, Schnohr, Claudia S., E-mail: c.schnohr@uni-jena.de, Lauermann, Iver, Rubio, Angel, Fritz Haber Institute, Max Planck Society, Faradayweg 4-6, 14195 Berlin, and Johnson, Benjamin, E-mail: benjamin.johnson@alumni.tu-berlin.de. Local versus global electronic properties of chalcopyrite alloys: X-ray absorption spectroscopy and ab initio calculations. United States: N. p., 2014. Web. doi:10.1063/1.4893579.
Sarmiento-Pérez, Rafael, Botti, Silvana, E-mail: silvana.botti@univ-lyon1.fr, Schnohr, Claudia S., E-mail: c.schnohr@uni-jena.de, Lauermann, Iver, Rubio, Angel, Fritz Haber Institute, Max Planck Society, Faradayweg 4-6, 14195 Berlin, & Johnson, Benjamin, E-mail: benjamin.johnson@alumni.tu-berlin.de. Local versus global electronic properties of chalcopyrite alloys: X-ray absorption spectroscopy and ab initio calculations. United States. doi:10.1063/1.4893579.
Sarmiento-Pérez, Rafael, Botti, Silvana, E-mail: silvana.botti@univ-lyon1.fr, Schnohr, Claudia S., E-mail: c.schnohr@uni-jena.de, Lauermann, Iver, Rubio, Angel, Fritz Haber Institute, Max Planck Society, Faradayweg 4-6, 14195 Berlin, and Johnson, Benjamin, E-mail: benjamin.johnson@alumni.tu-berlin.de. 2014. "Local versus global electronic properties of chalcopyrite alloys: X-ray absorption spectroscopy and ab initio calculations". United States. doi:10.1063/1.4893579.
@article{osti_22314387,
title = {Local versus global electronic properties of chalcopyrite alloys: X-ray absorption spectroscopy and ab initio calculations},
author = {Sarmiento-Pérez, Rafael and Botti, Silvana, E-mail: silvana.botti@univ-lyon1.fr and Schnohr, Claudia S., E-mail: c.schnohr@uni-jena.de and Lauermann, Iver and Rubio, Angel and Fritz Haber Institute, Max Planck Society, Faradayweg 4-6, 14195 Berlin and Johnson, Benjamin, E-mail: benjamin.johnson@alumni.tu-berlin.de},
abstractNote = {Element-specific unoccupied electronic states of Cu(In, Ga)S{sub 2} were studied as a function of the In/Ga ratio by combining X-ray absorption spectroscopy with density functional theory calculations. The S absorption edge shifts with changing In/Ga ratio as expected from the variation of the band gap. In contrast, the cation edge positions are largely independent of composition despite the changing band gap. This unexpected behavior is well reproduced by our calculations and originates from the dependence of the electronic states on the local atomic environment. The changing band gap arises from a changing spatial average of these localized states with changing alloy composition.},
doi = {10.1063/1.4893579},
journal = {Journal of Applied Physics},
number = 9,
volume = 116,
place = {United States},
year = 2014,
month = 9
}
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