Physics – Condensed Matter – Strongly Correlated Electrons
Scientific paper
2007-01-30
Phys. Rev. B 75, 094511 (2007)
Physics
Condensed Matter
Strongly Correlated Electrons
10 pages
Scientific paper
10.1103/PhysRevB.75.094511
Based 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 $\Gamma$ point of the first Brillouin zone forms. Correspondingly, in addition to a large Fermi surface an electron pocket close to the $\Gamma$ 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.
Anisimov Vladimir I.
Brenig Wolfram
Eremin Ilya
Korshunov Maxim M.
Renner Marcus
No associations
LandOfFree
Itinerant in-plane magnetic fluctuations and many-body correlations in Na$_x$CoO$_2$ does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Itinerant in-plane magnetic fluctuations and many-body correlations in Na$_x$CoO$_2$, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Itinerant in-plane magnetic fluctuations and many-body correlations in Na$_x$CoO$_2$ will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-470219