We study by Variational Monte Carlo an extended Hubbard model away from half filled band density which contains two competing nearest-neighbor interactions: a superexchange J favoring d-wave superconductivity and a repulsion V opposing against it. We find that the on-site repulsion U effectively enhances the strength of J meanwhile suppressing that of V, thus favoring superconductivity. This result shows that attractions which do not involve charge fluctuations are very well equipped against strong electron-electron repulsion so much to get advantage from it.
Increasing d-wave superconductivity by on-site repulsion / Plekhanov, E; Sorella, Sandro; Fabrizio, Michele. - In: PHYSICAL REVIEW LETTERS. - ISSN 0031-9007. - 90:18(2003), pp. 1-4. [10.1103/PhysRevLett.90.187004]
Increasing d-wave superconductivity by on-site repulsion
Sorella, Sandro;Fabrizio, Michele
2003-01-01
Abstract
We study by Variational Monte Carlo an extended Hubbard model away from half filled band density which contains two competing nearest-neighbor interactions: a superexchange J favoring d-wave superconductivity and a repulsion V opposing against it. We find that the on-site repulsion U effectively enhances the strength of J meanwhile suppressing that of V, thus favoring superconductivity. This result shows that attractions which do not involve charge fluctuations are very well equipped against strong electron-electron repulsion so much to get advantage from it.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
