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arXiv · 1410.5909

Finger-gate manipulated quantum transport in Dirac materials

Ioannis Kleftogiannis·Chi-Shung Tang·Shun-Jen Cheng
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Abstract

We investigate the quantum transport properties of multichannel nanoribbons made of materials described by the Dirac equation, under an in-plane magnetic field. In the low energy regime, positive and negative finger-gate potentials allow the electrons to make intra-subband transitions via hole-like or electron-like quasibound states (QBS), respectively, resulting in dips in the conductance. In the high energy regime, double dip structures in the conductance are found, attributed to spin-flip or spin-nonflip inter-subband transitions through the QBSs. Inverting the finger-gate polarity offers the possibility to manipulate the spin polarized electronic transport to achieve a controlled spin-switch.

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Ioannis Kleftogiannis, Chi-Shung Tang, Shun-Jen Cheng. 2014-10-22. Finger-gate manipulated quantum transport in Dirac materials. https://doi.org/10.1088/0953-8984/27/20/205302

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