Abstract Submitted for the MAR14 Meeting of The American Physical Society Dependence of interfacial conduction on oxygen annealing in MBE-grown LaAlO3/SrTiO3 heterostructures1

Submitted for the MAR14 Meeting of The American Physical Society Dependence of interfacial conduction on oxygen annealing in MBE-grown LaAlO3/SrTiO3 heterostructures1 HAO ZHANG, University of Toronto, JOSEPH NGAI, CHARLES AHN, Yale University, CHRISTOPHER MCMAHON, DAVID G. HAWTHORN, University of Waterloo, J.Y.T. WEI, University of Toronto and Canadian Institute for Advanced Research — The observation of interfacial metallicity in thin-film heterostructures of LaAlO3 (LAO) and SrTiO3 (STO) has sparked great interest in recent years. This metallicity has been attributed to electronic reconstruction induced by interfacial polar discontinuity [1]. However, the intrinsic oxygen variability of STO is also believed to influence the conduction of LAO/STO films [2], especially in films grown by pulsed laser deposition which can induce defects in STO [3]. To better understand the role of such defects, we study LAO films of varying thickness grown on STO by molecular beam epitaxy and post-annealed in oxygen. X-ray photoelectron spectroscopy is used to correlate the atomic valences with the conduction properties, in an effort to relate the interfacial electronic structure with the presence of oxygen vacancies. [1] J. Mannhart et al., MRS Bull. 33, 1027 (2008) [2] A. Kalabukhov et al., Phys. Rev. B 75, 121404 (2007) [3] Y. Chen et al., Nano Letters 11, 4 3774 (2011) 1Work supported by NSERC, CFI/OIT, and the Canadian Institute for Advanced Research. Hao Zhang University of Toronto Date submitted: 15 Nov 2013 Electronic form version 1.4