通过在非极性复杂氧化物界面处的应变诱导极化来创建高迁移率二维电子气。

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

机构信息

Department of Energy Conversion and Storage, Technical University of Denmark , Risø Campus, 4000 Roskilde, Denmark.

出版信息

Nano Lett. 2015 Mar 11;15(3):1849-54. doi: 10.1021/nl504622w. Epub 2015 Feb 20.

Abstract

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 cm(2) V(-1) s(-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.

摘要

在 SrTiO3 基异质结构中发现二维电子气 (2DEG) 为纳米电子学提供了新的机会。在此，我们通过在原本非极性钙钛矿型 CaZrO3/SrTiO3 异质界面处的外延应变诱导极化，产生了一种新型的氧化物 2DEG。值得注意的是，这种异质界面原子级平整，并在低温下表现出超过 60,000 cm(2) V(-1) s(-1) 的高电子迁移率。2DEG 载流子密度表现出对薄膜厚度的临界依赖性，与极化诱导 2DEG 方案吻合良好。