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arXiv · 0709.1991

Dephasing in a quantum dot coupled to a quantum point contact

Tomosuke Aono
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Abstract

We investigate a dephasing mechanism in a quantum dot capacitively coupled to a quantum point contact. We use a model which was proposed to explain the 0.7 structure in point contacts, based on the presence of a quasi-bound state in a point contact. The dephasing rate is examined in terms of charge fluctuations of electrons in the bound state. We address a recent experiment by Avinun-Kalish {\it et al.} [Phys. Rev. Lett. {\bf 92}, 156801 (2004)], where a double peak structure appears in the suppressed conductance through the quantum dot. We show that the two conducting channels induced by the bound state are responsible for the peak structure.

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Tomosuke Aono. 2007-09-13. Dephasing in a quantum dot coupled to a quantum point contact. https://doi.org/10.1103/physrevb.77.081303

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