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Title: Spatial-symmetry-induced dark states and charge trapping effects in the coupled quantum dots

Abstract

In a system of N interacting single-level quantum dots (QDs), we study the relaxation dynamics and the current–voltage characteristics determined by symmetry properties of the QD arrangement. Different numbers of dots, initial charge configurations, and various coupling regimes to reservoirs are considered. We reveal that effective charge trapping occurs for particular regimes of coupling to the reservoir when more than two dots form a ring structure with the C{sub N} spatial symmetry. We reveal that the effective charge trapping caused by the C{sub N} spatial symmetry of N coupled QDs depends on the number of dots and the way of coupling to the reservoirs. We demonstrate that the charge trapping effect is directly connected with the formation of dark states, which are not coupled to reservoirs due to the system spatial symmetry C{sub N}. We also reveal the symmetry blockade of the tunneling current caused by the presence of dark states.

Authors:
;  [1];  [2]
  1. Moscow State University (Russian Federation)
  2. Russian Academy of Sciences, Lebedev Physical Institute (Russian Federation)
Publication Date:
OSTI Identifier:
22617241
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Experimental and Theoretical Physics; Journal Volume: 122; Journal Issue: 6; Other Information: Copyright (c) 2016 Pleiades Publishing, Inc.; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; CONFIGURATION; COUPLING; CURRENTS; EFFECTIVE CHARGE; QUANTUM DOTS; RELAXATION; SYMMETRY; TRAPPING; TUNNEL EFFECT

Citation Formats

Maslova, N. S., Mantsevich, V. N., E-mail: vmantsev@gmail.com, and Arseev, P. I. Spatial-symmetry-induced dark states and charge trapping effects in the coupled quantum dots. United States: N. p., 2016. Web. doi:10.1134/S1063776116060169.
Maslova, N. S., Mantsevich, V. N., E-mail: vmantsev@gmail.com, & Arseev, P. I. Spatial-symmetry-induced dark states and charge trapping effects in the coupled quantum dots. United States. doi:10.1134/S1063776116060169.
Maslova, N. S., Mantsevich, V. N., E-mail: vmantsev@gmail.com, and Arseev, P. I. 2016. "Spatial-symmetry-induced dark states and charge trapping effects in the coupled quantum dots". United States. doi:10.1134/S1063776116060169.
@article{osti_22617241,
title = {Spatial-symmetry-induced dark states and charge trapping effects in the coupled quantum dots},
author = {Maslova, N. S. and Mantsevich, V. N., E-mail: vmantsev@gmail.com and Arseev, P. I.},
abstractNote = {In a system of N interacting single-level quantum dots (QDs), we study the relaxation dynamics and the current–voltage characteristics determined by symmetry properties of the QD arrangement. Different numbers of dots, initial charge configurations, and various coupling regimes to reservoirs are considered. We reveal that effective charge trapping occurs for particular regimes of coupling to the reservoir when more than two dots form a ring structure with the C{sub N} spatial symmetry. We reveal that the effective charge trapping caused by the C{sub N} spatial symmetry of N coupled QDs depends on the number of dots and the way of coupling to the reservoirs. We demonstrate that the charge trapping effect is directly connected with the formation of dark states, which are not coupled to reservoirs due to the system spatial symmetry C{sub N}. We also reveal the symmetry blockade of the tunneling current caused by the presence of dark states.},
doi = {10.1134/S1063776116060169},
journal = {Journal of Experimental and Theoretical Physics},
number = 6,
volume = 122,
place = {United States},
year = 2016,
month = 6
}
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