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arXiv · 0811.1624

On the Origin of the 2DEG Carrier Density at the LaAlO$_3$/SrTiO$_3$ Interface

Zoran S. Popović·Sashi Satpathy·Richard M. Martin
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Abstract

Transport measurements of the two-dimensional electron gas (2DEG) at the LaAlO$_3$/SrTiO$_3$ interface have found a density of carriers much lower than expected from the "polar catastrophe" arguments. From a detail density-functional study, we suggest how this discrepancy may be reconciled. We find that electrons occupy multiple subbands at the interface leading to a rich array of transport properties. Some electrons are confined to a single interfacial layer and susceptible to localization, while others with small masses and extended over several layers are expected to contribute to transport.

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Zoran S. Popović, Sashi Satpathy, Richard M. Martin. 2008-12-09. On the Origin of the 2DEG Carrier Density at the LaAlO$_3$/SrTiO$_3$ Interface. https://arxiv.org/abs/0811.1624

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