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arXiv · 1511.01348

Edge-state Blockade of Transport in Quantum Dot Arrays

Mónica Benito·Michael Niklas·Gloria Platero·Sigmund Kohler
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Abstract

We propose a transport blockade mechanism in quantum dot arrays and conducting molecules based on an interplay of Coulomb repulsion and the formation of edge states. As a model we employ a dimer chain that exhibits a topological phase transition. The connection to a strongly biased electron source and drain enables transport. We show that the related emergence of edge states is manifest in the shot noise properties as it is accompanied by a crossover from bunched electron transport to a Poissonian process. For both regions we develop a scenario that can be captured by a rate equation. The resulting analytical expressions for the Fano factor agree well with the numerical solution of a full quantum master equation.

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Mónica Benito, Michael Niklas, Gloria Platero, Sigmund Kohler. 2015-11-04. Edge-state Blockade of Transport in Quantum Dot Arrays. https://doi.org/10.1103/physrevb.93.115432

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