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arXiv · 1911.12174

Bias-induced chiral current and topological blockadein triple quantum dots

YuanDong Wang·ZhenGang Zhu·JianHua Wei·YiJing Yan
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Abstract

We theoretically investigate the quantum transport properties of a triangular triple quantum dot (TTQD) ring connected with two reservoirs by means of analytical derivation and accurate hierarchical-equations-of-motion calculation. A bias-induced chiral current in the absence of magnetic field is firstly demonstrated, which results from that the coupling between spin gauge field and spin current in the nonequilibrium TTQD induces a scalar spin chirality that lifts the chiral degeneracy and thus the time inversion symmetry. The chiral current is proved to oscillate with bias within the Coulomb blockade regime, which opens a possibility to control the chiral spin qubit by use of purely electrical manipulations. Then, a topological blockade of the transport current due to the localization of chiral states is elucidated by spectral function analysis. Finally, as a measurable character, the magnetoelectric susceptibility in our system is found about two orders of magnitude larger than that in a typical magnetoelectric material at low temperature.

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YuanDong Wang, ZhenGang Zhu, JianHua Wei, YiJing Yan. 2019-11-27. Bias-induced chiral current and topological blockadein triple quantum dots. https://doi.org/10.1209/0295-5075%2F130%2F17003

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