Electronic properties of buried hetero-interfaces of LaAlO3 on SrTiO3

Abstract

We have made very thin films of LaAlO3 on TiO2 terminated SrTiO3 and have measured the properties of the resulting interface in various ways. Transport measurements show a maximum sheet carrier density of 1016 cm-2 and a mobility around 104 cm2 V-1 s-1. In situ ultraviolet photoelectron spectroscopy (UPS) indicates that for these samples a finite density of states exists at the Fermi level. From the oxygen pressure dependence measured in both transport as well as the UPS, we detail, as reported previously by us, that oxygen vacancies play an important role in the creation of the charge carriers and that these vacancies are introduced by the pulsed laser deposition process used to make the heterointerfaces. Under the conditions studied the effect of LaAlO3 on the carrier density is found to be minimal.

19 pages, 6 figures

References in corpus (3)

• Magnetic effects at the interface between nonmagnetic oxides
• Origin of charge density at LaAlO3-on-SrTiO3 hetero-interfaces; possibility of intrinsic doping
• Photoemission from buried interfaces in SrTiO3/LaTiO3 superlattices

Cited by in corpus (10)

• Origin of Metallic States at Heterointerface between Band Insulators LaAlO${}_3$ and SrTiO${}_3$
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• Exponential decay of relaxation effects at LaAlO3/SrTiO3 heterointerfaces
• Structural and transport properties of highly Ru-deficient SrRu0.7O3 thin films prepared by molecular beam epitaxy: comparison with stoichiometric SrRuO3
• Enhanced spin-orbit coupling and charge carrier density suppression in LaAl1-xCrxO3/SrTiO3 heterointerfaces
• Thermally activated recovery of electrical conductivity in LaAlO3/SrTiO3
• Relaxor characteristics at the interfaces of [NdMnO3/SrMnO3/LaMnO3] superlattices
• Interplay between sheet resistance increase and magnetotransport properties in $\mathrm{LaAl}{\mathrm{O}}_3/\mathrm{SrTi}{\mathrm{O}}_3$
• Magnetothermopower of $\delta$-doped LaTiO${}_3$/SrTiO${}_3$ interfaces in the Kondo regime
• Temperature dependent giant resistance anomaly in LaAlO3/SrTiO3 nanostructures