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arXiv:1103.6228 · Physical Review B

Phonon-mediated decoherence in triple quantum dot interferometers

Fernando Domínguez, Sigmund Kohler, Gloria Platero

Published Jun 10, 2011• 23 citations
arXivHTMLPDF

Abstract

We investigate decoherence in a triple quantum dot in a ring configuration, in which one dot is coupled to a damped phonon mode while the other two dots are connected to a source and a drain, respectively. In the absence of decoherence, single-electron transport may get blocked by an electron falling into a superposition decoupled from the drain; this is known as a dark state. Phonon-mediated decoherence affects this superposition and leads to a finite current. We study the current and its shot noise numerically within a master equation approach for the electrons and the dissipative phonon mode. A polaron transformation allows us to obtain a reduced equation for only the dot electrons, which provides analytical results in agreement with numerical ones.

DOI
10.1103/physrevb.83.235319

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