Photonassisted tunneling in an asymmetrically coupled triple quantum dot
Abstract
The gatedefined 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 photonassisted tunneling process appear not only in the lefttocentral dot transition region but also in the lefttoright dot transition region. These sidebands are both attributed to the lefttocentral 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 twodimensional charge stability diagram; this will be helpful in future studies of the scalability of quantum dot systems.
 Authors:
 Key Laboratory of Quantum Information, CAS, University of Science and Technology of China, Hefei, Anhui 230026 (China)
 (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; TWODIMENSIONAL CALCULATIONS
Citation Formats
Wang, BaoChuan, Cao, Gang, Email: gcao@ustc.edu.cn, Chen, BaoBao, Yu, GuoDong, Li, HaiOu, Xiao, Ming, Guo, GuoPing, Email: gpguo@ustc.edu.cn, and Synergetic Innovation Center of Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei, Anhui 230026. Photonassisted tunneling in an asymmetrically coupled triple quantum dot. United States: N. p., 2016.
Web. doi:10.1063/1.4960453.
Wang, BaoChuan, Cao, Gang, Email: gcao@ustc.edu.cn, Chen, BaoBao, Yu, GuoDong, Li, HaiOu, Xiao, Ming, Guo, GuoPing, Email: gpguo@ustc.edu.cn, & Synergetic Innovation Center of Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei, Anhui 230026. Photonassisted tunneling in an asymmetrically coupled triple quantum dot. United States. doi:10.1063/1.4960453.
Wang, BaoChuan, Cao, Gang, Email: gcao@ustc.edu.cn, Chen, BaoBao, Yu, GuoDong, Li, HaiOu, Xiao, Ming, Guo, GuoPing, Email: 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.
"Photonassisted tunneling in an asymmetrically coupled triple quantum dot". United States.
doi:10.1063/1.4960453.
@article{osti_22597700,
title = {Photonassisted tunneling in an asymmetrically coupled triple quantum dot},
author = {Wang, BaoChuan and Cao, Gang, Email: gcao@ustc.edu.cn and Chen, BaoBao and Yu, GuoDong and Li, HaiOu and Xiao, Ming and Guo, GuoPing, Email: 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 gatedefined 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 photonassisted tunneling process appear not only in the lefttocentral dot transition region but also in the lefttoright dot transition region. These sidebands are both attributed to the lefttocentral 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 twodimensional 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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