Eur. Phys. J. B (2016) 89: 59
https://doi.org/10.1140/epjb/e2016-60872-5

Regular Article

Magnetic switching and spin filtering in an edge-state device based on HgTe waveguides

¹ Department of Physics, Zhejiang Normal University, Jinhua 321004, P.R. China
² Department of Physics and Institute for Functional Nanomaterials, University of Puerto Rico, Mayaguez, PR 00681, USA

^a e-mail: jin198810052216@163.com

Received: 5 November 2015
Received in final form: 11 January 2016
Published online: 2 March 2016

Abstract

We investigate theoretically the edge channel transport in a HgTe waveguide modulated by two magnetic barriers. For an electron incident from a quantum-spin-Hall state in leads, the transmission can depend strongly on the relative orientation (parallel or antiparallel) of the two magnetic barriers as its energy is near the bulk conduction band of leads. For the antiparallel configuration, the transmission is spin-independent and can be suppressed drastically. For the parallel configuration, the electron can transmit nearly perfectly for a proper spin orientation. This contrast in transmission indicates that the proposed edge-state device may serve as a magnetic switch and a spin filter.