Assessing the effective relevance of multiband effects in fullerides is of fundamental importance in understanding the complex properties of these compounds. In this paper we investigate the role of the multiband effects on the electron-phonon (el-ph) properties of the t(1u) bands coupled with the Jahn-Teller intramolecular H-g vibrational modes in C-60 compounds. We show that, assuming perfect degeneracy of the electronic bands, vertex diagrams arising from the breakdown of the adiabatic hypothesis, are one order of magnitude smaller than the noncrossing terms usually retained in the Migdal-Eliashberg (ME) theory. These results permit to understand the robustness of the ME theory found by numerical calculations. The effects of the nondegeneracy of the t(1u) in realistic systems are also analyzed. Using a tight-binding model we show that the el-ph interaction is mainly dominated by intraband scattering within a single electronic band. Our results question the reliability of a degenerate band modeling and show the importance of these combined effects in the A(3)C(60) family.

Relevance of multiband Jahn-Teller effects on the electron-phonon interaction in A3C60 / Cappelluti, E.; Paci, P.; Grimaldi, C.; Pietronero, Luciano. - In: PHYSICAL REVIEW. B, CONDENSED MATTER AND MATERIALS PHYSICS. - ISSN 1098-0121. - STAMPA. - 72:5(2005). [10.1103/PhysRevB.72.054521]

Relevance of multiband Jahn-Teller effects on the electron-phonon interaction in A3C60

P. PACI
;
PIETRONERO, Luciano
2005

Abstract

Assessing the effective relevance of multiband effects in fullerides is of fundamental importance in understanding the complex properties of these compounds. In this paper we investigate the role of the multiband effects on the electron-phonon (el-ph) properties of the t(1u) bands coupled with the Jahn-Teller intramolecular H-g vibrational modes in C-60 compounds. We show that, assuming perfect degeneracy of the electronic bands, vertex diagrams arising from the breakdown of the adiabatic hypothesis, are one order of magnitude smaller than the noncrossing terms usually retained in the Migdal-Eliashberg (ME) theory. These results permit to understand the robustness of the ME theory found by numerical calculations. The effects of the nondegeneracy of the t(1u) in realistic systems are also analyzed. Using a tight-binding model we show that the el-ph interaction is mainly dominated by intraband scattering within a single electronic band. Our results question the reliability of a degenerate band modeling and show the importance of these combined effects in the A(3)C(60) family.
2005
Superconductivity; Fullerides
01 Pubblicazione su rivista::01a Articolo in rivista
Relevance of multiband Jahn-Teller effects on the electron-phonon interaction in A3C60 / Cappelluti, E.; Paci, P.; Grimaldi, C.; Pietronero, Luciano. - In: PHYSICAL REVIEW. B, CONDENSED MATTER AND MATERIALS PHYSICS. - ISSN 1098-0121. - STAMPA. - 72:5(2005). [10.1103/PhysRevB.72.054521]
File allegati a questo prodotto
File Dimensione Formato  
Cappelluti_Relevance_2005.pdf

accesso aperto

Note: https://doi.org/10.1103/PhysRevB.72.054521
Tipologia: Versione editoriale (versione pubblicata con il layout dell'editore)
Licenza: Tutti i diritti riservati (All rights reserved)
Dimensione 139.52 kB
Formato Adobe PDF
139.52 kB Adobe PDF
VE_2005_11573-1746.pdf

solo gestori archivio

Tipologia: Versione editoriale (versione pubblicata con il layout dell'editore)
Licenza: Tutti i diritti riservati (All rights reserved)
Dimensione 139.52 kB
Formato Adobe PDF
139.52 kB Adobe PDF   Contatta l'autore

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11573/1746
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 4
  • ???jsp.display-item.citation.isi??? 4
social impact