Itinerant in-plane magnetic fluctuations and many-body correlations in Na$_x$CoO$_2$

Simple item page
dc.creatorKorshunov, M. M.
dc.creatorEremin, I.
dc.creatorShorikov, A.
dc.creatorAnisimov, V. I.
dc.creatorRenner, M.
dc.creatorBrenig, W.
dc.date2007-01-30
dc.date.accessioned2026-07-07T08:23:28Z
dc.date.available2026-07-07T08:23:28Z
dc.descriptionBased on the {\it ab-initio} band structure for Na$_x$CoO$_2$ we derive the single-electron energies and the effective tight-binding description for the $t_{2g}$ bands using projection procedure. Due to the presence of the next-nearest-neighbor hoppings a local minimum in the electronic dispersion close to the $Γ$ point of the first Brillouin zone forms. Correspondingly, in addition to a large Fermi surface an electron pocket close to the $Γ$ point emerges at high doping concentrations. The latter yields the new scattering channel resulting in a peak structure of the itinerant magnetic susceptibility at small momenta. This indicates dominant itinerant in-plane ferromagnetic fluctuations above certain critical concentration $x_m$, in agreement with neutron scattering data. Below $x_m$ the magnetic susceptibility shows a tendency towards the antiferromagnetic fluctuations. We further analyze the many-body effects on the electronic and magnetic excitations using various approximations applicable for different $U/t$ ratio.
dc.description10 pages
dc.identifierhttps://arxiv.org/abs/cond-mat/0701755
dc.identifierhttp://arxiv.org/abs/cond-mat/0701755
dc.identifierPhys. Rev. B 75, 094511 (2007)
dc.identifierdoi:10.1103/PhysRevB.75.094511
dc.identifier.urihttp://salesiana.dossiersoluciones.com/handle/123456789/136007
dc.subjectStrongly Correlated Electrons
dc.subjectSuperconductivity
dc.titleItinerant in-plane magnetic fluctuations and many-body correlations in Na$_x$CoO$_2$
dc.typetext

Files

Collections

arXiv