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Title: Epitaxial growth and thermodynamic stability of SrIrO{sub 3}/SrTiO{sub 3} heterostructures

Abstract

Obtaining high-quality thin films of 5d transition metal oxides is essential to explore the exotic semimetallic and topological phases predicted to arise from the combination of strong electron correlations and spin-orbit coupling. Here, we show that the transport properties of SrIrO{sub 3} thin films, grown by pulsed laser deposition, can be optimized by considering the effect of laser-induced modification of the SrIrO{sub 3} target surface. We further demonstrate that bare SrIrO{sub 3} thin films are subject to degradation in air and are highly sensitive to lithographic processing. A crystalline SrTiO{sub 3} cap layer deposited in-situ is effective in preserving the film quality, allowing us to measure metallic transport behavior in films with thicknesses down to 4 unit cells. In addition, the SrTiO{sub 3} encapsulation enables the fabrication of devices such as Hall bars without altering the film properties, allowing precise (magneto)transport measurements on micro- and nanoscale devices.

Authors:
; ; ; ;  [1];  [2]; ;  [3]
  1. Kavli Institute of Nanoscience, Delft University of Technology, P.O. Box 5046, 2600 GA Delft (Netherlands)
  2. Department of Quantum Matter Physics, University of Geneva, 24 Quai Ernest-Ansermet, 1211 Genève 4 (Switzerland)
  3. Van der Waals-Zeeman Institute, Institute of Physics (IoP), University of Amsterdam, Science Park 904, 1098 XH Amsterdam (Netherlands)
Publication Date:
OSTI Identifier:
22594371
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 109; Journal Issue: 4; 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; 75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; AIR; DEPOSITS; ELECTRON CORRELATION; ENERGY BEAM DEPOSITION; EPITAXY; LASER RADIATION; LASERS; LAYERS; L-S COUPLING; NANOSTRUCTURES; PULSED IRRADIATION; SPIN; STABILITY; STRONTIUM OXIDES; STRONTIUM TITANATES; THICKNESS; THIN FILMS; TOPOLOGY; TRANSITION ELEMENTS

Citation Formats

Groenendijk, D. J., E-mail: d.j.groenendijk@tudelft.nl, Manca, N., Mattoni, G., Kootstra, L., Caviglia, A. D., Gariglio, S., Huang, Y., and Heumen, E. van. Epitaxial growth and thermodynamic stability of SrIrO{sub 3}/SrTiO{sub 3} heterostructures. United States: N. p., 2016. Web. doi:10.1063/1.4960101.
Groenendijk, D. J., E-mail: d.j.groenendijk@tudelft.nl, Manca, N., Mattoni, G., Kootstra, L., Caviglia, A. D., Gariglio, S., Huang, Y., & Heumen, E. van. Epitaxial growth and thermodynamic stability of SrIrO{sub 3}/SrTiO{sub 3} heterostructures. United States. doi:10.1063/1.4960101.
Groenendijk, D. J., E-mail: d.j.groenendijk@tudelft.nl, Manca, N., Mattoni, G., Kootstra, L., Caviglia, A. D., Gariglio, S., Huang, Y., and Heumen, E. van. 2016. "Epitaxial growth and thermodynamic stability of SrIrO{sub 3}/SrTiO{sub 3} heterostructures". United States. doi:10.1063/1.4960101.
@article{osti_22594371,
title = {Epitaxial growth and thermodynamic stability of SrIrO{sub 3}/SrTiO{sub 3} heterostructures},
author = {Groenendijk, D. J., E-mail: d.j.groenendijk@tudelft.nl and Manca, N. and Mattoni, G. and Kootstra, L. and Caviglia, A. D. and Gariglio, S. and Huang, Y. and Heumen, E. van},
abstractNote = {Obtaining high-quality thin films of 5d transition metal oxides is essential to explore the exotic semimetallic and topological phases predicted to arise from the combination of strong electron correlations and spin-orbit coupling. Here, we show that the transport properties of SrIrO{sub 3} thin films, grown by pulsed laser deposition, can be optimized by considering the effect of laser-induced modification of the SrIrO{sub 3} target surface. We further demonstrate that bare SrIrO{sub 3} thin films are subject to degradation in air and are highly sensitive to lithographic processing. A crystalline SrTiO{sub 3} cap layer deposited in-situ is effective in preserving the film quality, allowing us to measure metallic transport behavior in films with thicknesses down to 4 unit cells. In addition, the SrTiO{sub 3} encapsulation enables the fabrication of devices such as Hall bars without altering the film properties, allowing precise (magneto)transport measurements on micro- and nanoscale devices.},
doi = {10.1063/1.4960101},
journal = {Applied Physics Letters},
number = 4,
volume = 109,
place = {United States},
year = 2016,
month = 7
}
  • Recent theory predictions of exotic band topologies in (111) honeycomb perovskite SrIrO{sub 3} layers sandwiched between SrTiO{sub 3} have garnered much attention in the condensed matter physics and materials communities. However, perovskite SrIrO{sub 3} film growth in the (111) direction remains unreported, as efforts to synthesize pure SrIrO{sub 3} on (111) perovskite substrates have yielded films with monoclinic symmetry rather than the perovskite structure required by theory predictions. In this study, we report the synthesis of ultra-thin metastable perovskite SrIrO{sub 3} films capped with SrTiO{sub 3} grown on (111) SrTiO{sub 3} substrates by pulsed laser deposition. The atomic structure ofmore » the ultra-thin films was examined with scanning transmission electron microscopy (STEM), which suggests a perovskite layering distinct from the bulk SrIrO{sub 3} monoclinic phase. In-plane 3-fold symmetry for the entire heterostructure was confirmed using synchrotron surface X-ray diffraction to measure symmetry equivalent crystal truncation rods. Our findings demonstrate the ability to stabilize (111) honeycomb perovskite SrIrO{sub 3}, which provides an experimental avenue to probe the phenomena predicted for this material system.« less
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