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Title: Tuning the electronic properties at the surface of BaBiO{sub 3} thin films

Abstract

The presence of 2D electron gases at surfaces or interfaces in oxide thin films remains a hot topic in condensed matter physics. In particular, BaBiO{sub 3} appears as a very interesting system as it was theoretically proposed that its (001) surface should become metallic if a Bi-termination is achieved (Vildosola et al., PRL 110, 206805 (2013)). Here we report on the preparation by pulsed laser deposition and characterization of BaBiO{sub 3} thin films on silicon. We show that the texture of the films can be tuned by controlling the growth conditions, being possible to stabilize strongly (100)-textured films. We find significant differences on the spectroscopic and transport properties between (100)-textured and non-textured films. We rationalize these experimental results by performing first principles calculations, which indicate the existence of electron doping at the (100) surface. This stabilizes Bi ions in a 3+ state, shortens Bi-O bonds and reduces the electronic band gap, increasing the surface conductivity. Our results emphasize the importance of surface effects on the electronic properties of perovskites, and provide strategies to design novel oxide heterostructures with potential interface-related 2D electron gases.

Authors:
 [1];  [2]; ; ;  [1];  [3]; ;  [4];  [2];  [5];  [1];  [1];  [6];
  1. GIyA y INN, CNEA, Av.Gral Paz 1499, (1650), San Martín, Buenos Aires (Argentina)
  2. (Argentina)
  3. (CONICET) (Argentina)
  4. Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET) (Argentina)
  5. CRISMAT, CNRS UMR 6508, ENSICAEN, 6 Boulevard Maréchal Juin, 14050 Caen Cedex 4 (France)
  6. (1650), San Martín, Buenos Aires (Argentina)
Publication Date:
OSTI Identifier:
22611567
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Advances; Journal Volume: 6; Journal Issue: 6; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; BARIUM COMPOUNDS; BISMUTH COMPOUNDS; DESIGN; ELECTRICAL PROPERTIES; ENERGY BEAM DEPOSITION; GASES; INTERFACES; LASER RADIATION; OXIDES; OXYGEN COMPOUNDS; PEROVSKITES; PULSED IRRADIATION; PULSES; SILICON; SURFACE PROPERTIES; SURFACES; THIN FILMS

Citation Formats

Ferreyra, C., Departamento de Física, Facultad Ciencias Exactas y Naturales, Universidad de Buenos Aires, Guller, F., Llois, A. M., Vildosola, V., Consejo Nacional de Investigaciones Científicas y Técnicas, Marchini, F., Williams, F. J., Departamento de Química Inorgánica, Analítica y Química-Física, INQUIMAE-CONICET, Facultad Ciencias Exactas y Naturales, Universidad de Buenos Aires, Pabellón 2, Ciudad Universitaria, Buenos Aires, Lüders, U., Albornoz, C., Leyva, A. G., Escuela de Ciencia y Tecnología, UNSAM, Campus Miguelete,, and and others. Tuning the electronic properties at the surface of BaBiO{sub 3} thin films. United States: N. p., 2016. Web. doi:10.1063/1.4954037.
Ferreyra, C., Departamento de Física, Facultad Ciencias Exactas y Naturales, Universidad de Buenos Aires, Guller, F., Llois, A. M., Vildosola, V., Consejo Nacional de Investigaciones Científicas y Técnicas, Marchini, F., Williams, F. J., Departamento de Química Inorgánica, Analítica y Química-Física, INQUIMAE-CONICET, Facultad Ciencias Exactas y Naturales, Universidad de Buenos Aires, Pabellón 2, Ciudad Universitaria, Buenos Aires, Lüders, U., Albornoz, C., Leyva, A. G., Escuela de Ciencia y Tecnología, UNSAM, Campus Miguelete,, & and others. Tuning the electronic properties at the surface of BaBiO{sub 3} thin films. United States. doi:10.1063/1.4954037.
Ferreyra, C., Departamento de Física, Facultad Ciencias Exactas y Naturales, Universidad de Buenos Aires, Guller, F., Llois, A. M., Vildosola, V., Consejo Nacional de Investigaciones Científicas y Técnicas, Marchini, F., Williams, F. J., Departamento de Química Inorgánica, Analítica y Química-Física, INQUIMAE-CONICET, Facultad Ciencias Exactas y Naturales, Universidad de Buenos Aires, Pabellón 2, Ciudad Universitaria, Buenos Aires, Lüders, U., Albornoz, C., Leyva, A. G., Escuela de Ciencia y Tecnología, UNSAM, Campus Miguelete,, and and others. 2016. "Tuning the electronic properties at the surface of BaBiO{sub 3} thin films". United States. doi:10.1063/1.4954037.
@article{osti_22611567,
title = {Tuning the electronic properties at the surface of BaBiO{sub 3} thin films},
author = {Ferreyra, C. and Departamento de Física, Facultad Ciencias Exactas y Naturales, Universidad de Buenos Aires and Guller, F. and Llois, A. M. and Vildosola, V. and Consejo Nacional de Investigaciones Científicas y Técnicas and Marchini, F. and Williams, F. J. and Departamento de Química Inorgánica, Analítica y Química-Física, INQUIMAE-CONICET, Facultad Ciencias Exactas y Naturales, Universidad de Buenos Aires, Pabellón 2, Ciudad Universitaria, Buenos Aires and Lüders, U. and Albornoz, C. and Leyva, A. G. and Escuela de Ciencia y Tecnología, UNSAM, Campus Miguelete, and and others},
abstractNote = {The presence of 2D electron gases at surfaces or interfaces in oxide thin films remains a hot topic in condensed matter physics. In particular, BaBiO{sub 3} appears as a very interesting system as it was theoretically proposed that its (001) surface should become metallic if a Bi-termination is achieved (Vildosola et al., PRL 110, 206805 (2013)). Here we report on the preparation by pulsed laser deposition and characterization of BaBiO{sub 3} thin films on silicon. We show that the texture of the films can be tuned by controlling the growth conditions, being possible to stabilize strongly (100)-textured films. We find significant differences on the spectroscopic and transport properties between (100)-textured and non-textured films. We rationalize these experimental results by performing first principles calculations, which indicate the existence of electron doping at the (100) surface. This stabilizes Bi ions in a 3+ state, shortens Bi-O bonds and reduces the electronic band gap, increasing the surface conductivity. Our results emphasize the importance of surface effects on the electronic properties of perovskites, and provide strategies to design novel oxide heterostructures with potential interface-related 2D electron gases.},
doi = {10.1063/1.4954037},
journal = {AIP Advances},
number = 6,
volume = 6,
place = {United States},
year = 2016,
month = 6
}
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