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arXiv · 1210.7497

Toward an artificial Mott insulator: Correlations in confined, high-density electron liquids in SrTiO3

Pouya Moetakef·Clayton A. Jackson·Jinwoo Hwang·Leon Balents·S. James Allen·Susanne Stemmer
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Abstract

We investigate correlation physics in high-density, two-dimensional electron liquids that reside in narrow SrTiO3 quantum wells. The quantum wells are remotely doped via an interfacial polar discontinuity and the three-dimensional (3D) carrier density is modulated by changing the width of the quantum well. It is shown that even at 3D densities well below one electron per site, short-range Coulomb interactions become apparent in transport, and an insulating state emerges at a critical density. We also discuss the role of disorder in the insulating state.

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Pouya Moetakef, Clayton A. Jackson, Jinwoo Hwang, Leon Balents, S. James Allen, Susanne Stemmer. 2012-10-28. Toward an artificial Mott insulator: Correlations in confined, high-density electron liquids in SrTiO3. https://doi.org/10.1103/physrevb.86.201102

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