Electron pairing in small Hubbard Clusters.

POSTER

Abstract

Exact thermal studies of 4-site Hubbard Nanoclusters are carried out using the analytical eigenvalues. Electron pairing is seen when the on-site Coulomb interaction is smaller than a critical value Uc(T) in the repulsive Hubbard clusters which also show spin pairing at a lower temperature. Specific heat and probability calculations provide strong support for the existence of competing (paired and unpaired) phases near optimal doping. Attractive 4-site Hubbard model can be mapped on to the repulsive model and these studies can be used to understand ferroelectricity in certain metal clusters.

Authors

  • Kalum Palandage

    • University of Connecticut
    • Department of Physics, University of Connecticut

  • Gayanath Fernando

    • University of Connecticut
    • Department of Physics, University of Connecticut

  • Armen Kocharian

    • California State University

  • Jim Davenport

    • Brookhaven National Lab
    • Computational Science Center, Brookhaven National
    • Computational Science Center, Brookhaven National Laboratory