title: Dynamic defect correlations dominate activated electronic transport in SrTiO3.
abstract: Strontium titanate (SrTiO3, STO) is a critically important material for the study of emergent electronic phases in complex oxides, as well as for the development of applications based on their heterostructures. Despite the large body of knowledge on STO, there are still many uncertainties regarding the role of defects in the properties of STO, including their influence on ferroelectricity in bulk STO and ferromagnetism in STO-based heterostructures. We present a detailed analysis of the decay of persistent photoconductivity in STO single crystals with defect concentrations that are relatively low but significantly affect their electronic properties. The results show that photo-activated electron transport cannot be described by a superposition of the properties due to independent point defects as current models suggest but is, instead, governed by defect complexes that interact through dynamic correlations. These results emphasize the importance of defect correlations for activated electronic transport properties of semiconducting and insulating perovskite oxides.
authors.affiliation: Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA.|Department of Physics and Astronomy, University of Tennessee Knoxville, Tennessee 37996, USA.
authors.forename: Paul C
authors.initials: PC
authors.lastname: Snijders
authors.affiliation: Department of Physics, Lamar University, Beaumont, Texas 77710, USA.
authors.forename: Cengiz
authors.initials: C
authors.lastname: Şen
authors.affiliation: Department of Physics and Astronomy, University of Tennessee Knoxville, Tennessee 37996, USA.
authors.forename: Michael P
authors.initials: MP
authors.lastname: McConnell
authors.affiliation: Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA.
authors.forename: Ying-Zhong
authors.initials: YZ
authors.lastname: Ma
authors.affiliation: Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA.
authors.forename: Andrew F
authors.initials: AF
authors.lastname: May
authors.affiliation: Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA.
authors.forename: Andreas
authors.initials: A
authors.lastname: Herklotz
authors.affiliation: Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA.
authors.forename: Anthony T
authors.initials: AT
authors.lastname: Wong
authors.affiliation: Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA.
authors.forename: T Zac
authors.initials: TZ
authors.lastname: Ward