Gate controlled spin pumping at a quantum spin Hall edge

Awadhesh Narayan; Aaron Hurley; Stefano Sanvito

doi:10.1063/1.4824068

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arXiv · 1311.7329

Gate controlled spin pumping at a quantum spin Hall edge

Awadhesh Narayan·Aaron Hurley·Stefano Sanvito

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Abstract

We propose a four-terminal device designed to manipulate by all electrical means the spin of a magnetic adatom positioned at the edge of a quantum spin Hall insulator. We show that an electrical gate, able to tune the interface resistance between a quantum spin Hall insulator and the source and drain electrodes, can switch the device between two regimes: one where the system exhibits spin pumping and the other where the adatom remains in its ground state. This demonstrates an all-electrical route to control single spins by exploiting helical edge states of topological materials.

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Awadhesh Narayan, Aaron Hurley, Stefano Sanvito. 2013-11-28. Gate controlled spin pumping at a quantum spin Hall edge. https://doi.org/10.1063/1.4824068

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