skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Small hole polarons in rare-earth titanates

Abstract

We investigate the behavior of hole polarons in rare-earth titanates by combining optical conductivity measurements with first-principles hybrid density functional calculations. Sr-doped GdTiO{sub 3} (Gd{sub 1−x}Sr{sub x}TiO{sub 3}) was grown by molecular beam epitaxy. We show that a feature in the optical conductivity that was previously identified with the Mott-Hubbard gap is actually associated with the excitation of a small polaron. The assignment is based on an excellent match between the experimental spectra and first-principles calculations for polaron excitation mechanisms.

Authors:
; ; ; ; ; ;  [1]; ;  [2]
  1. Materials Department, University of California Santa Barbara, California 91306-5050 (United States)
  2. Department of Physics, University of California, Santa Barbara, California 91306-5050 (United States)
Publication Date:
OSTI Identifier:
22423750
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 106; Journal Issue: 23; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; 77 NANOSCIENCE AND NANOTECHNOLOGY; DENSITY FUNCTIONAL METHOD; DOPED MATERIALS; EXCITATION; GADOLINIUM COMPOUNDS; HOLES; MOLECULAR BEAM EPITAXY; POLARONS; RARE EARTHS; STRONTIUM; TITANATES; TITANIUM OXIDES

Citation Formats

Bjaalie, L., Moetakef, P., Cain, T. A., Janotti, A., Himmetoglu, B., Stemmer, S., Van de Walle, C. G., Ouellette, D. G., and Allen, S. J. Small hole polarons in rare-earth titanates. United States: N. p., 2015. Web. doi:10.1063/1.4922316.
Bjaalie, L., Moetakef, P., Cain, T. A., Janotti, A., Himmetoglu, B., Stemmer, S., Van de Walle, C. G., Ouellette, D. G., & Allen, S. J. Small hole polarons in rare-earth titanates. United States. doi:10.1063/1.4922316.
Bjaalie, L., Moetakef, P., Cain, T. A., Janotti, A., Himmetoglu, B., Stemmer, S., Van de Walle, C. G., Ouellette, D. G., and Allen, S. J. 2015. "Small hole polarons in rare-earth titanates". United States. doi:10.1063/1.4922316.
@article{osti_22423750,
title = {Small hole polarons in rare-earth titanates},
author = {Bjaalie, L. and Moetakef, P. and Cain, T. A. and Janotti, A. and Himmetoglu, B. and Stemmer, S. and Van de Walle, C. G. and Ouellette, D. G. and Allen, S. J.},
abstractNote = {We investigate the behavior of hole polarons in rare-earth titanates by combining optical conductivity measurements with first-principles hybrid density functional calculations. Sr-doped GdTiO{sub 3} (Gd{sub 1−x}Sr{sub x}TiO{sub 3}) was grown by molecular beam epitaxy. We show that a feature in the optical conductivity that was previously identified with the Mott-Hubbard gap is actually associated with the excitation of a small polaron. The assignment is based on an excellent match between the experimental spectra and first-principles calculations for polaron excitation mechanisms.},
doi = {10.1063/1.4922316},
journal = {Applied Physics Letters},
number = 23,
volume = 106,
place = {United States},
year = 2015,
month = 6
}