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arXiv · 1407.0924

Dephasing-assisted transport in linear triple quantum dots

L. D. Contreras-Pulido·M. Bruderer·S. F. Huelga·M. B. Plenio
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Abstract

Environmental noise usually hinders the efficiency of charge transport through coherent quantum systems; an exception is dephasing-assisted transport (DAT). We show that linear triple quantum dots in a transport configuration and subjected to pure dephasing exhibit DAT if the coupling to the drain reservoir exceeds a threshold. DAT occurs for arbitrarily weak dephasing and the enhancement can be directly controlled by the coupling to the drain. Moreover, for specific settings, the enhanced current is accompanied by a reduction in relative shot noise. We identify the quantum Zeno effect and long-distance tunnelling as underlying dynamical processes involved in dephasing-assisted and -suppressed transport. Our analytical results are obtained by using the density matrix formalism and the characteristic polynomial approach to full counting statistics.

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L. D. Contreras-Pulido, M. Bruderer, S. F. Huelga, M. B. Plenio. 2014-10-08. Dephasing-assisted transport in linear triple quantum dots. https://doi.org/10.1088/1367-2630%2F16%2F11%2F113061

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