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arXiv · 1111.2245

Transport through a quantum spin Hall quantum dot

Carsten Timm
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Abstract

Quantum spin Hall insulators, recently realized in HgTe/(Hg,Cd)Te quantum wells, support topologically protected, linearly dispersing edge states with spin-momentum locking. A local magnetic exchange field can open a gap for the edge states. A quantum-dot structure consisting of two such magnetic tunneling barriers is proposed and the charge transport through this device is analyzed. The effects of a finite bias voltage beyond linear response, of a gate voltage, and of the charging energy in the quantum dot are studied within a combination of Green-function and master-equation approaches. Among other results, a partial recurrence of non-interacting behavior is found for strong interactions, and the possibility of controlling the edge magnetization by a locally applied gate voltage is proposed.

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Carsten Timm. 2011-11-09. Transport through a quantum spin Hall quantum dot. https://doi.org/10.1103/physrevb.86.155456

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