Sandia National Laboratories, Livermore, California 94551, United States.
Nano Lett. 2011 Aug 10;11(8):3074-9. doi: 10.1021/nl200981x. Epub 2011 Jun 30.
The electronic properties of heterojunction electron gases formed in GaN/AlGaN core/shell nanowires with hexagonal and triangular cross sections are studied theoretically. We show that at nanoscale dimensions, the nonpolar hexagonal system exhibits degenerate quasi-one-dimensional electron gases at the hexagon corners, which transition to a core-centered electron gas at lower doping. In contrast, polar triangular core/shell nanowires show either a nondegenerate electron gas on the polar face or a single quasi-one-dimensional electron gas at the corner opposite the polar face, depending on the termination of the polar face. More generally, our results indicate that electron gases in closed nanoscale systems are qualitatively different from their bulk counterparts.
本文从理论上研究了具有六方和三角横截面的 GaN/AlGaN 核/壳纳米线中形成的异质结电子气的电子特性。我们表明，在纳米尺度上，非极性六方体系在六方角处表现出简并的准一维电子气，在较低掺杂时过渡到以核为中心的电子气。相比之下，极性三角核/壳纳米线在极性面上表现出非简并电子气，或者在与极性面相对的角处表现出单个准一维电子气，这取决于极性面的终止方式。更一般地说，我们的结果表明，封闭纳米尺度系统中的电子气在性质上与它们的体对应物不同。
