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Title: Electric field control of the γ-Al{sub 2}O{sub 3}/SrTiO{sub 3} interface conductivity at room temperature

Abstract

Controlling interfaces using electric fields is at the heart of modern electronics. The discovery of the conducting interface between the two insulating oxides LaAlO{sub 3} (LAO) and SrTiO{sub 3} (STO) has led to a number of interesting electric field-dependent phenomena. Recently, it was shown that replacing LAO with a spinel γ-Al{sub 2}O{sub 3} (GAO) allows a good pseudo-epitaxial film growth and high electron mobility at low temperatures. Here, we show that the GAO/STO interface resistance, similar to LAO/STO, can be tuned by orders of magnitude at room temperature using the electric field of a backgate. The resistance change is non-volatile, bipolar, and can be tuned continuously rather than being a simple on/off switch. Exposure to light significantly changes the capabilities to tune the interface resistance. High- and low-resistive states are obtained by annihilation and creation, respectively, of free n-type carriers, and we speculate that electromigration of oxygen vacancies is the origin of the tunability.

Authors:
; ; ; ;  [1]; ;  [2]
  1. Department of Energy Conversion and Storage, Technical University of Denmark, Risø Campus, DK-4000 Roskilde (Denmark)
  2. Niels Bohr Institute, Center for Quantum Devices, University of Copenhagen, DK-2100 Copenhagen Ø (Denmark)
Publication Date:
OSTI Identifier:
22590592
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 109; Journal Issue: 2; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; ALUMINIUM OXIDES; ELECTRIC FIELDS; ELECTRON MOBILITY; ELECTROPHORESIS; FILMS; GALLIUM OXIDES; INTERFACES; LANTHANUM OXIDES; SPINELS; STRONTIUM TITANATES; SWITCHES; TEMPERATURE RANGE 0273-0400 K; VACANCIES; VISIBLE RADIATION

Citation Formats

Christensen, D. V., E-mail: dechr@dtu.dk, Trier, F., Soosten, M. von, Chen, Y. Z., Pryds, N., Prawiroatmodjo, G. E. D. K., and Jespersen, T. S. Electric field control of the γ-Al{sub 2}O{sub 3}/SrTiO{sub 3} interface conductivity at room temperature. United States: N. p., 2016. Web. doi:10.1063/1.4955490.
Christensen, D. V., E-mail: dechr@dtu.dk, Trier, F., Soosten, M. von, Chen, Y. Z., Pryds, N., Prawiroatmodjo, G. E. D. K., & Jespersen, T. S. Electric field control of the γ-Al{sub 2}O{sub 3}/SrTiO{sub 3} interface conductivity at room temperature. United States. doi:10.1063/1.4955490.
Christensen, D. V., E-mail: dechr@dtu.dk, Trier, F., Soosten, M. von, Chen, Y. Z., Pryds, N., Prawiroatmodjo, G. E. D. K., and Jespersen, T. S. 2016. "Electric field control of the γ-Al{sub 2}O{sub 3}/SrTiO{sub 3} interface conductivity at room temperature". United States. doi:10.1063/1.4955490.
@article{osti_22590592,
title = {Electric field control of the γ-Al{sub 2}O{sub 3}/SrTiO{sub 3} interface conductivity at room temperature},
author = {Christensen, D. V., E-mail: dechr@dtu.dk and Trier, F. and Soosten, M. von and Chen, Y. Z. and Pryds, N. and Prawiroatmodjo, G. E. D. K. and Jespersen, T. S.},
abstractNote = {Controlling interfaces using electric fields is at the heart of modern electronics. The discovery of the conducting interface between the two insulating oxides LaAlO{sub 3} (LAO) and SrTiO{sub 3} (STO) has led to a number of interesting electric field-dependent phenomena. Recently, it was shown that replacing LAO with a spinel γ-Al{sub 2}O{sub 3} (GAO) allows a good pseudo-epitaxial film growth and high electron mobility at low temperatures. Here, we show that the GAO/STO interface resistance, similar to LAO/STO, can be tuned by orders of magnitude at room temperature using the electric field of a backgate. The resistance change is non-volatile, bipolar, and can be tuned continuously rather than being a simple on/off switch. Exposure to light significantly changes the capabilities to tune the interface resistance. High- and low-resistive states are obtained by annihilation and creation, respectively, of free n-type carriers, and we speculate that electromigration of oxygen vacancies is the origin of the tunability.},
doi = {10.1063/1.4955490},
journal = {Applied Physics Letters},
number = 2,
volume = 109,
place = {United States},
year = 2016,
month = 7
}
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