http://www.cnr.it/ontology/cnr/individuo/prodotto/ID458

Isotope effects in the Hubbard-Holstein model within dynamical mean-field theory (Articolo in rivista)

Type

Label

Isotope effects in the Hubbard-Holstein model within dynamical mean-field theory (Articolo in rivista) (literal)

Anno

Http://www.cnr.it/ontology/cnr/pubblicazioni.owl#doi

Alternative label

P. Paci (1); M. Capone (2,3); E. Cappelluti (2,3); S. Ciuchi (4,2); C. Grimaldi (5,6) (2006)
Isotope effects in the Hubbard-Holstein model within dynamical mean-field theory
in Physical review. B, Condensed matter and materials physics
(literal)

Http://www.cnr.it/ontology/cnr/pubblicazioni.owl#autori

P. Paci (1); M. Capone (2,3); E. Cappelluti (2,3); S. Ciuchi (4,2); C. Grimaldi (5,6) (literal)

Pagina inizio

Pagina fine

Http://www.cnr.it/ontology/cnr/pubblicazioni.owl#url

Http://www.cnr.it/ontology/cnr/pubblicazioni.owl#numeroVolume

Rivista

Http://www.cnr.it/ontology/cnr/pubblicazioni.owl#pagineTotali

Http://www.cnr.it/ontology/cnr/pubblicazioni.owl#numeroFascicolo

Note

Http://www.cnr.it/ontology/cnr/pubblicazioni.owl#affiliazioni

(1) International School for Advanced Studies (SISSA), via Beirut 2-4, 34014 Trieste, Italy (2) SMC-INFM and Istituto dei Sistemi Complessi, CNR, via dei Taurini 19, 00185 Roma, Italy (3) Dipartimento di Fisica, Università \"La Sapienza,\" Piazzale A. Moro 2, 00185 Roma, Italy (4) Dipartimento di Fisica, Università de L'Aquila and INFM UdR AQ, 67010 Coppito-L'Aquila, Italy (5) Ecole Polytechnique Fédérale de Lausanne, LPM, Station 17, CH-1015 Lausanne, Switzerland (6) DPMC, Université de Genève, 24 quai Ernest Ansermet, CH-1211 Genève 4, Switzerland (literal)

Titolo

Isotope effects in the Hubbard-Holstein model within dynamical mean-field theory (literal)

Abstract

We study the isotope effects arising from the coupling of correlated electrons with dispersionless phonons by considering the Hubbard-Holstein model at half-filling within the dynamical mean-field theory. In particular we calculate the isotope effects on the quasiparticle spectral weight Z, the renormalized phonon frequency, and the static charge and spin susceptibilities. In the weakly correlated regime U/t less than or similar to 1.5, where U is the Hubbard repulsion and t is the bare electron half-bandwidth, the physical properties are qualitatively similar to those characterizing the Holstein model in the absence of Coulomb repulsion, where the bipolaronic binding takes place at large electron-phonon coupling and it is reflected in divergent isotope responses. On the contrary in the strongly correlated regime U/t greater than or similar to 1.5, where the bipolaronic metal-insulator transition becomes of first order, the isotope effects are bounded, suggesting that the first-order transition is likely driven by an electronic mechanism, rather then by a lattice instability. These results point out how the isotope responses are extremely sensitive to phase boundaries and they may be used to characterize the competition between the electron-phonon coupling and the Hubbard repulsion. (literal)

Prodotto di