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Title: Photon-assisted tunneling in an asymmetrically coupled triple quantum dot

Abstract

The gate-defined quantum dot is regarded as one of the basic structures required for scalable semiconductor quantum processors. Here, we demonstrate a structure that contains three quantum dots scaled in series. The electron number of each dot and the tunnel coupling between them can be tuned conveniently using splitting gates. We tune the quantum dot array asymmetrically such that the tunnel coupling between the right dot and the central dot is much larger than that between the left dot and the central dot. When driven by microwaves, the sidebands of the photon-assisted tunneling process appear not only in the left-to-central dot transition region but also in the left-to-right dot transition region. These sidebands are both attributed to the left-to-central transition for asymmetric coupling. Our result shows that there is a region of a triple quantum dot structure that remains indistinct when studied with a normal two-dimensional charge stability diagram; this will be helpful in future studies of the scalability of quantum dot systems.

Authors:
; ; ; ; ; ;  [1];  [2]
  1. Key Laboratory of Quantum Information, CAS, University of Science and Technology of China, Hefei, Anhui 230026 (China)
  2. (China)
Publication Date:
OSTI Identifier:
22597700
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 120; Journal Issue: 6; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; ASYMMETRY; COUPLING; DIAGRAMS; ELECTRONS; MICROWAVE RADIATION; PHOTONS; QUANTUM DOTS; SEMICONDUCTOR MATERIALS; TUNNEL EFFECT; TWO-DIMENSIONAL CALCULATIONS

Citation Formats

Wang, Bao-Chuan, Cao, Gang, E-mail: gcao@ustc.edu.cn, Chen, Bao-Bao, Yu, Guo-Dong, Li, Hai-Ou, Xiao, Ming, Guo, Guo-Ping, E-mail: gpguo@ustc.edu.cn, and Synergetic Innovation Center of Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei, Anhui 230026. Photon-assisted tunneling in an asymmetrically coupled triple quantum dot. United States: N. p., 2016. Web. doi:10.1063/1.4960453.
Wang, Bao-Chuan, Cao, Gang, E-mail: gcao@ustc.edu.cn, Chen, Bao-Bao, Yu, Guo-Dong, Li, Hai-Ou, Xiao, Ming, Guo, Guo-Ping, E-mail: gpguo@ustc.edu.cn, & Synergetic Innovation Center of Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei, Anhui 230026. Photon-assisted tunneling in an asymmetrically coupled triple quantum dot. United States. doi:10.1063/1.4960453.
Wang, Bao-Chuan, Cao, Gang, E-mail: gcao@ustc.edu.cn, Chen, Bao-Bao, Yu, Guo-Dong, Li, Hai-Ou, Xiao, Ming, Guo, Guo-Ping, E-mail: gpguo@ustc.edu.cn, and Synergetic Innovation Center of Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei, Anhui 230026. 2016. "Photon-assisted tunneling in an asymmetrically coupled triple quantum dot". United States. doi:10.1063/1.4960453.
@article{osti_22597700,
title = {Photon-assisted tunneling in an asymmetrically coupled triple quantum dot},
author = {Wang, Bao-Chuan and Cao, Gang, E-mail: gcao@ustc.edu.cn and Chen, Bao-Bao and Yu, Guo-Dong and Li, Hai-Ou and Xiao, Ming and Guo, Guo-Ping, E-mail: gpguo@ustc.edu.cn and Synergetic Innovation Center of Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei, Anhui 230026},
abstractNote = {The gate-defined quantum dot is regarded as one of the basic structures required for scalable semiconductor quantum processors. Here, we demonstrate a structure that contains three quantum dots scaled in series. The electron number of each dot and the tunnel coupling between them can be tuned conveniently using splitting gates. We tune the quantum dot array asymmetrically such that the tunnel coupling between the right dot and the central dot is much larger than that between the left dot and the central dot. When driven by microwaves, the sidebands of the photon-assisted tunneling process appear not only in the left-to-central dot transition region but also in the left-to-right dot transition region. These sidebands are both attributed to the left-to-central transition for asymmetric coupling. Our result shows that there is a region of a triple quantum dot structure that remains indistinct when studied with a normal two-dimensional charge stability diagram; this will be helpful in future studies of the scalability of quantum dot systems.},
doi = {10.1063/1.4960453},
journal = {Journal of Applied Physics},
number = 6,
volume = 120,
place = {United States},
year = 2016,
month = 8
}
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