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arXiv · 1402.2747

Ferromagnetic barrier induced negative differential conductance on the surface of a topological insulator

Xing-Tao An
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Abstract

We theoretically investigate the effect of the negative differential conductance of a ferromagnetic barrier on the surface of a topological insulator. Due to the changes of the shape and position of the Fermi surfaces in the ferromagnetic barrier, the transport processes can be divided into three kinds: the total, partial and blockade transmission mechanisms. The bias voltage can give rise to the transition of the transport processes from partial to blockade transmission mechanisms, which results in a giant effect of negative differential conductance. With appropriate structural parameters, the current-voltage characteristics show that the minimum value of the current can reach to zero in a wide range of the bias voltage, and a large peak-to-valley current ratio can be obtained.

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Xing-Tao An. 2014-02-12. Ferromagnetic barrier induced negative differential conductance on the surface of a topological insulator. https://doi.org/10.1088/1674-1056/23/10/107301

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