Björnson Kristofer, Black-Schaffer Annica M
Department of Physics and Astronomy, Uppsala University, Box 516, S-751 20 Uppsala, Sweden.
Niels Bohr Institute, University of Copenhagen, Juliane Maries Vej 30, DK-2100 Copenhagen, Denmark.
Beilstein J Nanotechnol. 2018 May 25;9:1558-1563. doi: 10.3762/bjnano.9.147. eCollection 2018.
We show conceptually that the edge of a two-dimensional topological insulator can be used to construct a solid-state Stern-Gerlach spin splitter. By threading such a Stern-Gerlach apparatus with a magnetic flux, Aharanov-Bohm-like interference effects are introduced. Using ferromagnetic leads, the setup can be used to both measure magnetic flux and as a spintronics switch. With normal metallic leads a switchable spintronics NOT-gate can be implemented. Furthermore, we show that a sequence of such devices can be used to construct a single-qubit SU(2)-gate, one of the two gates required for a universal quantum computer. The field sensitivity, or switching field, , is related to the characteristic size of the device, , through = /(2π), with being the unit of electric charge.
我们从概念上表明，二维拓扑绝缘体的边缘可用于构建固态斯特恩-盖拉赫自旋分离器。通过用磁通量穿过这样一个斯特恩-盖拉赫装置，会引入类似阿哈罗诺夫-玻姆的干涉效应。使用铁磁引线，该装置既可以用于测量磁通量，也可以用作自旋电子学开关。使用普通金属引线，可以实现一个可切换的自旋电子学非门。此外，我们表明，一系列这样的器件可用于构建一个单量子比特的SU(2)门，这是通用量子计算机所需的两个门之一。场灵敏度或开关场(\Delta B)与器件的特征尺寸(L)通过(\Delta B = \hbar/(2\pi e L))相关，其中(e)是电荷单位。
