Spin-polarized tunneling current through a thin film of topological insulator in a parallel magnetic field

Sergey S. Pershoguba; Victor M. Yakovenko

doi:10.1103/physrevb.86.165404

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arXiv · 1206.4733

Spin-polarized tunneling current through a thin film of topological insulator in a parallel magnetic field

Sergey S. Pershoguba·Victor M. Yakovenko

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Abstract

We calculate the tunneling conductance σbetween the surface states on the opposite sides of the ultra-thin film of a topological insulator in a parallel magnetic field B_y. The parallel magnetic produces a relative shift of the in-plane momenta of the two surfaces states. An overlap between the shifted Fermi circles and their spin structure define an unusual dependence of the tunneling conductance σ(B_y) on the magnetic field. Because the spin of the electronic surface states in topological insulators is locked with momentum, the spin-polarization of the tunneling current can be controlled by magnetic field B_y.

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Sergey S. Pershoguba, Victor M. Yakovenko. 2012-09-03. Spin-polarized tunneling current through a thin film of topological insulator in a parallel magnetic field. https://doi.org/10.1103/physrevb.86.165404

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