Atomic and electronic structures of interfaces of complex oxides
EMSL Project ID
44701
Abstract
Oxide interfaces, superlattices and solid solutions provide opportunities for generating materials with novel properties, providing the atomic structures of the interface and near interface regions are well controlled. Current growth techniques have limited capabilities of controlling atomic scale processes and even post factum characterization of the interface disorder is difficult. In this regards, accurate predictions of thermodynamically stable interface structures, characterization of the interface structural disorder and its effect on the interface electronic properties would provide valuable complementary information and will guide further experimental work. Previous research has demonstrated that epitaxial film growth can be used to generate single interfaces and quasi-two-dimensional materials with novel properties. However, there is little understanding of the effects of cross-interface atom diffusion and structural disorder on the interface electronic properties. The primary objective of this project is to unravel the atomic scale mechanisms governing modification of the electronic properties of interfaces of two complex oxides upon inter-diffusion of metal atoms across the plane of the interface.
We will investigate electronic properties of realistic hetero-structures of LaCrO3 (LCO), LaFeO3 (LFO), and SrTiO3 (STO). The LCO and LFO are antiferromagnets, but their multilayers and interfaces with STO may exhibit ferromagnetism in some cases. In this project we will apply a range of empirical and ab initio computational methods in order to investigate the effect of the cation inter-diffusion and lattice defects, such as anion vacancies and nitrogen substitutional impurities, on the electronic and magnetic structures of LFO/LCO/STO interfaces and pinpoint the mechanisms of control over the interface properties. This theoretical work is integrated with an experimental EMSL project focused on these systems and employing several experimental capabilities available at EMSL.
Project Details
Project type
Large-Scale EMSL Research
Start Date
2011-10-01
End Date
2014-09-30
Status
Closed
Released Data Link
Team
Principal Investigator
Team Members
Related Publications
Chamberlin SE, Y Wang, KA Lopata, TC Kaspar, A Cohn, DR Gamelin, N Govind, PV Sushko, and SA Chambers. 2013. "Optical Absorption and Spectral Photoconductivity in ?-(Fe1-xCrx)2O3 Solid-Solution Thin Films." Journal of Physics: Condensed Matter 25(39):392002. doi:10.1088/0953-8984/25/39/392002
Chambers SA, M Gu, PV Sushko, H Yang, CM Wang, and ND Browning. 2013. "Ultra-low contact resistance at an epitaxial metal/oxide heterojunction through interstitial site doping." Advanced Materials 25(29):4001–4005. doi:10.1002/adma.201301030
Kaspar TC, SE Chamberlin, ME Bowden, RJ Colby, V Shutthanandan, S Manandhar, Y Wang, PV Sushko, and SA Chambers. 2014. "Impact of Lattice Mismatch and Stoichiometry on the Structure and Bandgap of (Fe,Cr)2O3 Epitaxial Thin Films." Journal of Physics: Condensed Matter 26(13):5005. doi:10.1088/0953-8984/26/13/135005
McLeod JA, A Buling, EZ Kurmaev, PV Sushko, N Neumann, LD Finkelstein, SW Kim, H Hosono, and A Moewes. 2012. "Spectroscopic Characterization of a Multiband Complex Oxide: Insulating and Conducting Cement 12CaO·7Al?O?." Physical Review. B, Condensed Matter and Materials Physics 85(4):045204 - 045212. doi:10.1103/PhysRevB.85.045204
McLeod JA, EZ Kurmaev, PV Sushko, TD Boyko, IA Levitsky, and A Moewes. 2012. "Selective Response of Mesoporous Silicon to Adsorbants with Nitro Groups." Chemistry - A European Journal 18(10):2912-2922. doi:10.1002/chem.201102084
Qiao L, H Zhang, ME Bowden, T Varga, V Shutthanandan, RJ Colby, Y Du, BC Kabius, PV Sushko, MD Biegalski, and SA Chambers. 2013. "The Impacts of Cation Stoichiometry and Substrate Surface Quality on Nucleation, Structure, Defect Formation, and Intermixing in Complex Oxide Heteroepitaxy–LaCrO 3 on SrTiO 3 (001)." Advanced Functional Materials. doi:10.1002/adfm.201202655
Sushko P, L Qiao, ME Bowden, T Varga, GJ Exarhos, FK Urban, III, D Barton, and SA Chambers. 2013. "Multiband Optical Absorption Controlled by Lattice Strain in Thin-Film LaCrO3." Physical Review Letters 110(7):077401. doi:10.1103/PhysRevLett.110.077401
Sushko PV. 2012. "Tuning Optical Properties of Complex Oxides: Examples of 12CaO.7Al2O3 Mayenite and LaCrO3 Perovskite." In Oxide-based Materials and Devices III, vol. 8263, ed. Ferechteh H. Teherani; David C. Look; David J. Rogers, pp. 8263-34. Proceedings of SPIE, Bellingham, WA. doi:10.1117/12.912844
Wang Y, KA Lopata, SA Chambers, N Govind, and PV Sushko. 2013. "Optical absorption and band gap reduction in (Fe1-xCrx)2O3 solid solutions: A first-principles study." Journal of Physical Chemistry C 117(48):25504-25512. doi:10.1021/jp407496w