Magnetism and Conductivity Along Structural Domain Walls of SrTiO3
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Abstract
The interface between the oxide insulators LaAlO3 and SrTiO3 (LAO/STO) hosts a two-dimensional electron gas. The combination of interfacial conductivity and superconductivity at ultra-low temperatures with the physical phenomena of the oxide parent materials has fueled extensive research in the field since its discovery in 2004. Scanning superconducting quantum interference device (SQUID) measurements have shown that structural domain walls, formed below 105 K, modulate the current flow at the interface and recently revealed weak magnetic signals along the same domain structure. Here we use scanning SQUID to investigate the temperature dependence of different electronic properties of the LAO/STO interface. We find correlation between magnetism and conductivity, which are both spatially modulated on the domain structure. This data suggests a possible relation between the populations of electrons participating in each order.
Keywords
Oxide interfaces Magnetism Conductivity Scanning SQUID microscopy Polarity FerroelectricityNotes
Funding Information
Y.F. and B.K. were supported by the European Research Council Grant No. ERC-2014-STG-639792, the Israeli Science Foundation grant no. ISF-1281/17, and the QuantERA ERA-NET Cofund in Quantum Technologies (Project No. 731473). Y.X. and H.Y.H. were supported by the U.S. Department of Energy, Office of Basic Energy Sciences, Division of Materials Sciences and Engineering, under contract no. DE-AC02-76SF00515.
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