Eur. Phys. J. B (2013) 86: 36
https://doi.org/10.1140/epjb/e2012-30508-1

Regular Article

Electron transport in a ferromagnetic/normal/ferromagnetic tunnel junction based on the surface of a topological insulator

¹ The department of Physics, Guangxi medical university, Nanning, Guangxi 530021, P.R. China
² School of Physics, Huazhong University of Science and Technology, Wuhan 430074, P.R. China

^a e-mail: jianhui831110@163.com

Received: 26 June 2012
Received in final form: 11 October 2012
Published online: 4 February 2013

Abstract

We theoretically study the electron transport properties in a ferromagnetic/normal/ferromagnetic tunnel junction, which is deposited on the top of a topological surface. The conductance at the parallel (P) configuration can be much bigger than that at the antiparallel (AP) configuration. Compared P with AP configuration, there exists a shift of phase which can be tuned by gate voltage. We find that the exchange field weakly affects the conductance of carriers for P configuration but can dramatically suppress the conductance of carriers for AP configuration. This controllable electron transport implies anomalous magnetoresistance in this topological spin valve, which may contribute to the development of spintronics. In addition, there shows an existence of Fabry-Perot-like electron interference in our model based on the topological insulator, which does not appear in the same model based on the two dimensional electron gas.