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Fractionally delta-doped oxide superlattices for higher carrier mobilities

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 نشر من قبل Woo Seok Choi
 تاريخ النشر 2012
  مجال البحث فيزياء
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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 interfaces 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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