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arXiv · 1302.1411

Evolution of variable range hopping in strongly localized two dimensional electron gas at NdAlO3/SrTiO3 (100) heterointerfaces

A. Annadi·A. Putra·A. Srivastava·X. Wang·Z. Huang·Z. Q. Liu·T. Venkatesan·Ariando
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Abstract

We report evolution of the two-dimensional electron gas behavior at the NdAlO3/SrTiO3 heterointerfaces with varying thicknesses of the NdAlO3 overlayer. The samples with a thicker NdAlO3 show strong localizations at low temperatures and the degree of localization is found to increase with the NdAlO3 thickness. The T -1/3 temperature dependence of the sheet resistance at low temperatures and the magnetoresistance study reveal that the conduction is governed by a two-dimensional variable range hopping mechanism in this strong localized regime. We attribute this thickness dependence of the transport properties of the NdAlO3/SrTiO3 interfaces to the interface strain induced by the overlayers.

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A. Annadi, A. Putra, A. Srivastava, X. Wang, Z. Huang, Z. Q. Liu, T. Venkatesan, Ariando. 2013-02-06. Evolution of variable range hopping in strongly localized two dimensional electron gas at NdAlO3/SrTiO3 (100) heterointerfaces. https://doi.org/10.1063/1.4768932

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