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arXiv · 1601.01009

Tunneling Planar Hall Effect in Topological Insulators: Spin-Valves and Amplifiers

Benedikt Scharf·Alex Matos-Abiague·Jong E. Han·Ewelina M. Hankiewicz·Igor Žutić
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Abstract

We investigate tunneling across a single ferromagnetic barrier on the surface of a three-dimensional topological insulator. In the presence of a magnetization component along the bias direction, a tunneling planar Hall conductance (TPHC), transverse to the applied bias, develops. Electrostatic control of the barrier enables a giant Hall angle, with the TPHC exceeding the longitudinal tunneling conductance. By changing the in-plane magnetization direction it is possible to change the sign of both the longitudinal and transverse differential conductance without opening a gap in the topological surface state. The transport in a topological insulator/ferromagnet junction can thus be drastically altered from a simple spin-valve to an amplifier.

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Benedikt Scharf, Alex Matos-Abiague, Jong E. Han, Ewelina M. Hankiewicz, Igor Žutić. 2016-10-14. Tunneling Planar Hall Effect in Topological Insulators: Spin-Valves and Amplifiers. https://doi.org/10.1103/physrevlett.117.166806

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