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arXiv · 1209.0721

Fractionally delta-doped oxide superlattices for higher carrier mobilities

Woo Seok Choi·Suyoun Lee·Valentino R. Cooper·Ho Nyung Lee
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Abstract

A 2D electron gas system in an oxide heterostructure serves as an important playground for novel phenomena. Here, we show that, by using fractional delta-doping to control the interface's composition in LaxSr1-xTiO3/SrTiO3 artificial oxide superlattices, the filling-controlled 2D insulator-metal transition can be realized. The atomic-scale control of d-electron band filling, which in turn contributes to the tuning of effective mass and density of the charge carriers, is found to be a fascinating route to substantially enhanced carrier mobilities.

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Woo Seok Choi, Suyoun Lee, Valentino R. Cooper, Ho Nyung Lee. 2012-09-04. Fractionally delta-doped oxide superlattices for higher carrier mobilities. https://doi.org/10.1021/nl301844z

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