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Creation of high mobility two-dimensional electron gases via strain induced polarization at an otherwise nonpolar complex oxide interface

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 نشر من قبل Yunzhong Chen
 تاريخ النشر 2015
  مجال البحث فيزياء
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The discovery of two-dimensional electron gases (2DEGs) in SrTiO3-based heterostructures provides new opportunities for nanoelectronics. Herein, we create a new type of oxide 2DEG by the epitaxial-strain-induced polarization at an otherwise nonpolar perovskite-type interface of CaZrO3/SrTiO3. Remarkably, this heterointerface is atomically sharp, and exhibits a high electron mobility exceeding 60,000 cm2V-1s-1 at low temperatures. The 2DEG carrier density exhibits a critical dependence on the film thickness, in good agreement with the polarization induced 2DEG scheme.



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