About

I am a Senior Research Scientist at the School of Physics, Georgia Institute of Technology. I have carried out theoretical research in the area of small, finite size systems at the intersection of Atomic and Molecular physics (trapped ultracold atoms and ions), Condensed Matter Physics (quantum dots, metal clusters, and graphene nanostructures), quantum chemical methods applied outside traditional Chemistry (unrestricted Hartree-Fock, Configuration Interaction), and Nuclear Many-Body Physics (second RPA and methodology of symmetry breaking and restoration).  Starting in 1999, Wigner molecularization, i.e., the formation and physical properties of quantum Wigner molecules in artificial condensed-matter and ultracold-atom nanosystems (due to strong repulsive interparticle correlations) has been a major focus of my research. My current projects: Wigner molecules and strong correlations in (1) ultracold-atom harmonic traps and lattices, (2) quantum-computer double-quantum-dot qubits, (3) jellybean (elongated) quantum dots, and (4) moiré superlattices.

Email: constantine.yannouleas [AT] physics.gatech.edu

LATEST RESEARCH ACTIVITY (SINCE 2021):

  1. C. Yannouleas and U. Landman,
    Exact closed-form analytic wave functions in two dimensions: Contact-interacting  fermionic spinful ultracold atoms in a rapidly rotating trap,
    Letter, Phys. Rev. Research 3, L032028 (2021),
    click here to download the published paper
    click here to download the paper from the arXiv e-print archive
    Using computer symbolic language and numerical exact diagonalization, the authors derive closed-form exact analytical solutions for two-dimensional spinful hard-core-repelling fermions under fractional quantum-Hall conditions, exhibiting intrinsic structure of Wigner molecules and spin anatomy of quantum skyrmions.
  2. C.Yannouleas, with J.A. Sheikh, J. Dobaczewski, P. Ring, and L.M. Robledo,
    Symmetry restoration in mean-field approaches,
    J. Phys. G: Nucl. Part. Phys. 48, 123001 (2021) (Topical review) [110 pages].
    A review of Symmetry Breaking & Restoration in both nuclei and condensed-matter nanosystems (e.g., quantum dots).
    click here to download the published review

    Wigner-molecule isomers [(2,7) and (1,8)] in a circular parabolic quantum dot with N=9 electrons (from Fig. 20 in Sec. 7).
    For more information click on the badge below:

  3. C. Yannouleas and U. Landman,
    Wigner molecules and hybrid qubits,
    Letter, J. Phys.: Condens. Matter 34, 21LT01 (2022).
    click here to download the published letter
    click here to see the paper on the IOPscience website
  4. C. Yannouleas and U. Landman,
    Molecular formations and spectra due to electron correlations in three-electron hybrid double-well qubits.
    Phys. Rev. B 105, 205302 (2022) [14 pages].
    click here to download the published paper
    click here to download the paper from the arXiv eprint archive
  5. C. Yannouleas and U. Landman,
    Valleytronic full configuration-interaction approach: Application to the excitation spectra of Si double-dot qubits,
    Phys. Rev. B 106, 195306 (2022) [19 pages].
    click here to download the published paper
    click here to download the paper from the arXiv eprint archive  
  6. C. Yannouleas and U. Landman,
    Quantum Wigner molecules in moiré materials,
    Letter, Physical Review B 108, L121411 (2023) [12 pages]
    click here to download the published paper
    click here to download the paper from the arXiv eprint archive
  7. EDITORS’ SUGGESTION
           Quantum Wigner molecules (WMs) in strongly interacting few-body fermionic moiré quantum dots in twisted bilayers of transition metal dichalcogenide (TMD) materials are uncovered via full configuration interaction calculations, going beyond the Aufbau principle of natural atoms and Hubbard modeling. Nested polygonal sliding rings of localized fermions, hidden in the exact particle densities, are revealed through wavefunction correlation analysis [see (3,9) and (1,6,10) electron WMs in 2D semiconductors], broadening the WM portfolio to include the TMD trilobal symmetry as an added resource in twistronics, and providing benchmarks for AI-based many-body computations.     Click here to see the tweet by the PRB Editors announcing the publication of this Letter.

  8. C. Yannouleas and U. Landman,
    Wigner-molecule supercrystal in transition-metal dichalcogenide moiré superlattices: Lessons from the bottom-up approach,
    Letter, Physical Review B 109, L121302 (2024) [9 pages],
    click here to download the published article (PDF)

    click here to download the paper from the arXiv eprint archive
  9. ======================================================================
    WIGNER MOLECULARIZATION AND WIGNER MOLECULES: REVIEW ARTICLES

    • C. Yannouleas and U. Landman,
    SYMMETRY BREAKING AND QUANTUM CORRELATIONS IN FINITE SYSTEMS:
    STUDIES OF QUANTUM DOTS AND ULTRACOLD BOSE GASES AND RELATED
    NUCLEAR AND CHEMICAL METHODS,
    Rep. Prog. Phys. 70 (2007) pp. 2067-2148
    click here to download the published paper (PDF)

    click here to see the article at the IOPscience website
    For more information click on the badge below:

    • C. Yannouleas and U. Landman,
    ELECTRON AND BOSON CLUSTERS IN CONFINED GEOMETRIES: SYMMETRY
    BREAKING IN QUANTUM DOTS AND HARMONIC TRAPS,
    Proc. Natl. Acad. Sci. (USA) 103 (2006) pp. 10600 – 10605 (Special Feature)
    click here to download the published article (PDF)

    • C. Yannouleas,
    For an up-to-date (end of 2020) review of the literature on Wigner molecules and strong e-e interactions, see Sec. 7 in publication No. 111 above
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    Please see the companion page below for additional information and the full record of previous publications:
    COMPANION PAGE: PROFESSIONAL PROFILE, RESEARCH INTERESTS, AND EARLIER PUBLICATIONS

    See also my Google Scholar webpage: click here
    See also publications posted on the ArXiv: click here
    See also my AD Scientific Index 2023 webpage: click here


    Unrestricted Hartree-Fock electron density in a parabolic quantum dot for the case of 19 electrons at zero magnetic field, exhibiting breaking of the circular symmetry and formation of a Wigner molecule (or Wigner crystallite). For details, see publication No. 68 in this URL
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    Last Updated: March 19, 2024, 3:23 pm EDT