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Title: Near-field scanning magneto-optical spectroscopy of Wigner molecules

Abstract

We study the emission spectra of single self-organized InP/GaInP QDs (size 100-220 nm) using high-spatial-resolution, low-temperature (5 K) near-field scanning optical microscope (NSOM) operating at magnetic field strength B=0-10 T. The dots contain up to twenty electrons and represent natural Wigner molecules (WM). We observed vibronic-type shake-up structure in single electron QDs manifesting formation of two electron (2e) WM in photo-excited state. We found that relative intensities of the shake-up components described well by vibronic Frank-Condon factors giving for dots having parabolic confinement energy ħω{sub 0}=1.2-4 meV molecule bond lengths 40-140 nm. We used measurements of magnetic-field-induced shifts to distinguish emission of 2e-WM and singly charged exciton (trion). We also observed magnetic-field-induced molecular-droplet transition for two electron dot, emitting through doubly charge exciton (tetron) at zero magnetic field.

Authors:
;  [1];  [2];  [1]; ; ; ; ; ;  [3];  [4]
  1. University of Notre Dame, Notre Dame, IN 46556 (United States)
  2. (Russian Federation)
  3. Ioffe Physical-Technical Institute of the Russian Academy of Sciences, Saint Petersburg, 194021 (Russian Federation)
  4. SPSMS, UMR-E CEA/UJF-Grenoble 1, INAC, Grenoble, FR-38054 (France)
Publication Date:
OSTI Identifier:
22609111
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Conference Proceedings; Journal Volume: 1748; Journal Issue: 1; Conference: STRANN 2016: 5. international conference on state-of-the-art trends of scientific research of artificial and natural nanoobjects, St. Petersburg (Russian Federation), 26-29 Apr 2016; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; BOND LENGTHS; CONFINEMENT; ELECTRONS; EMISSION; EMISSION SPECTRA; EXCITED STATES; GALLIUM COMPOUNDS; INDIUM PHOSPHIDES; MAGNETIC FIELDS; MOLECULES; OPTICAL MICROSCOPES; QUANTUM DOTS; SPATIAL RESOLUTION; SPECTROSCOPY; TEMPERATURE RANGE 0000-0013 K; WIGNER THEORY

Citation Formats

Mintairov, A. M., E-mail: amintair@nd.edu, Rouvimov, S., Ioffe Physical-Technical Institute of the Russian Academy of Sciences, Saint Petersburg, 194021, Kapaldo, J., Merz, J. L., Kalyygniy, N., Mintairov, S. A., Nekrasov, S., Saly, R., Vlasov, A. S., and Blundell, S.. Near-field scanning magneto-optical spectroscopy of Wigner molecules. United States: N. p., 2016. Web. doi:10.1063/1.4954335.
Mintairov, A. M., E-mail: amintair@nd.edu, Rouvimov, S., Ioffe Physical-Technical Institute of the Russian Academy of Sciences, Saint Petersburg, 194021, Kapaldo, J., Merz, J. L., Kalyygniy, N., Mintairov, S. A., Nekrasov, S., Saly, R., Vlasov, A. S., & Blundell, S.. Near-field scanning magneto-optical spectroscopy of Wigner molecules. United States. doi:10.1063/1.4954335.
Mintairov, A. M., E-mail: amintair@nd.edu, Rouvimov, S., Ioffe Physical-Technical Institute of the Russian Academy of Sciences, Saint Petersburg, 194021, Kapaldo, J., Merz, J. L., Kalyygniy, N., Mintairov, S. A., Nekrasov, S., Saly, R., Vlasov, A. S., and Blundell, S.. 2016. "Near-field scanning magneto-optical spectroscopy of Wigner molecules". United States. doi:10.1063/1.4954335.
@article{osti_22609111,
title = {Near-field scanning magneto-optical spectroscopy of Wigner molecules},
author = {Mintairov, A. M., E-mail: amintair@nd.edu and Rouvimov, S. and Ioffe Physical-Technical Institute of the Russian Academy of Sciences, Saint Petersburg, 194021 and Kapaldo, J. and Merz, J. L. and Kalyygniy, N. and Mintairov, S. A. and Nekrasov, S. and Saly, R. and Vlasov, A. S. and Blundell, S.},
abstractNote = {We study the emission spectra of single self-organized InP/GaInP QDs (size 100-220 nm) using high-spatial-resolution, low-temperature (5 K) near-field scanning optical microscope (NSOM) operating at magnetic field strength B=0-10 T. The dots contain up to twenty electrons and represent natural Wigner molecules (WM). We observed vibronic-type shake-up structure in single electron QDs manifesting formation of two electron (2e) WM in photo-excited state. We found that relative intensities of the shake-up components described well by vibronic Frank-Condon factors giving for dots having parabolic confinement energy ħω{sub 0}=1.2-4 meV molecule bond lengths 40-140 nm. We used measurements of magnetic-field-induced shifts to distinguish emission of 2e-WM and singly charged exciton (trion). We also observed magnetic-field-induced molecular-droplet transition for two electron dot, emitting through doubly charge exciton (tetron) at zero magnetic field.},
doi = {10.1063/1.4954335},
journal = {AIP Conference Proceedings},
number = 1,
volume = 1748,
place = {United States},
year = 2016,
month = 6
}
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