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Parallel-Coupled Quantum Dots in InAs Nanowires

Nilsson, Malin LU ; Chen, I. Ju LU ; Lehmann, Sebastian LU ; Maulerova, Vendula; Dick, Kimberly A. LU and Thelander, Claes LU (2017) In Nano Letters 17(12). p.7847-7852
Abstract

We use crystal-phase tuning during epitaxial growth of InAs nanowires to create quantum dots with very strong confinement. A set of gate electrodes are used to reproducibly split the quantum dots into even smaller pairs for which we can control the populations down to the last electron. The double quantum dots, which are parallel-coupled to source and drain, show clear and stable odd-even level pairing due to spin degeneracy and the strong confinement. The combination of hard-wall barriers to source and drain, shallow interdot tunnel barriers, and very high single-particle excitation energies allow an order of magnitude tuning of the strength for the first intramolecular bond. We show examples for nanowires with different facet... (More)

We use crystal-phase tuning during epitaxial growth of InAs nanowires to create quantum dots with very strong confinement. A set of gate electrodes are used to reproducibly split the quantum dots into even smaller pairs for which we can control the populations down to the last electron. The double quantum dots, which are parallel-coupled to source and drain, show clear and stable odd-even level pairing due to spin degeneracy and the strong confinement. The combination of hard-wall barriers to source and drain, shallow interdot tunnel barriers, and very high single-particle excitation energies allow an order of magnitude tuning of the strength for the first intramolecular bond. We show examples for nanowires with different facet orientations, and suggest possible mechanisms behind the reproducible double-dot formation.

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Please use this url to cite or link to this publication:
author
organization
publishing date
type
Contribution to journal
publication status
published
subject
keywords
artificial molecule, crystal structure control, InAs, nanowire, Parallel quantum dots
in
Nano Letters
volume
17
issue
12
pages
6 pages
publisher
The American Chemical Society
external identifiers
  • scopus:85037601647
  • wos:000418393300093
ISSN
1530-6992
DOI
10.1021/acs.nanolett.7b04090
language
English
LU publication?
yes
id
00cd6005-e53b-43be-a9b0-d9167dfcfa75
date added to LUP
2018-01-05 08:23:25
date last changed
2018-01-16 13:29:19
@article{00cd6005-e53b-43be-a9b0-d9167dfcfa75,
  abstract     = {<p>We use crystal-phase tuning during epitaxial growth of InAs nanowires to create quantum dots with very strong confinement. A set of gate electrodes are used to reproducibly split the quantum dots into even smaller pairs for which we can control the populations down to the last electron. The double quantum dots, which are parallel-coupled to source and drain, show clear and stable odd-even level pairing due to spin degeneracy and the strong confinement. The combination of hard-wall barriers to source and drain, shallow interdot tunnel barriers, and very high single-particle excitation energies allow an order of magnitude tuning of the strength for the first intramolecular bond. We show examples for nanowires with different facet orientations, and suggest possible mechanisms behind the reproducible double-dot formation.</p>},
  author       = {Nilsson, Malin and Chen, I. Ju and Lehmann, Sebastian and Maulerova, Vendula and Dick, Kimberly A. and Thelander, Claes},
  issn         = {1530-6992},
  keyword      = {artificial molecule,crystal structure control,InAs,nanowire,Parallel quantum dots},
  language     = {eng},
  month        = {12},
  number       = {12},
  pages        = {7847--7852},
  publisher    = {The American Chemical Society},
  series       = {Nano Letters},
  title        = {Parallel-Coupled Quantum Dots in InAs Nanowires},
  url          = {http://dx.doi.org/10.1021/acs.nanolett.7b04090},
  volume       = {17},
  year         = {2017},
}