Accession Number:

ADA265101

Title:

The Mechanism of Pairing in Hubbard Molecules

Descriptive Note:

Corporate Author:

NAVAL COMMAND CONTROL AND OCEAN SURVEILLANCE CENTER RDT AND E DIV SAN DIEGO CA

Personal Author(s):

Report Date:

1993-03-01

Pagination or Media Count:

4.0

Abstract:

There exist many calculations for finite Hubbard clusters that do find pairing of electrons. At the same time, pairing is found to be absent in many other molecules. We have tried to find the mechanism of pairing by doing systematic calculations for a large number of Hubbard molecules. It is found that there exist two different mechanisms of pairing, corresponding to pairing occurring at small U and vanishing at large U, and to pairing occurring only at large U. We find that the small-U pairing cannot be discussed without simultaneously discussing the Jahn-Teller distortions of the Hubbard molecules. Calculations that find pairing do so because they neglect the Jahn-Teller distortions of the molecules, and the pairing vanishes when the distortion is included in the model. The large-U pairing, surprisingly, is related neither to Jahn-Teller distortion nor to antiferromagnetism. Implications for high Tc oxides and doped C60 will be discussed. Author

Subject Categories:

  • Inorganic Chemistry
  • Electricity and Magnetism
  • Atomic and Molecular Physics and Spectroscopy

Distribution Statement:

APPROVED FOR PUBLIC RELEASE