Spin- and Charge Excitations of the Triangular Hubbard-Model: a FLEX-Study
| dc.creator | Renner, Marcus | |
| dc.creator | Brenig, Wolfram | |
| dc.date | 2003-10-10 | |
| dc.date | 2003-10-12 | |
| dc.date.accessioned | 2026-07-07T02:54:08Z | |
| dc.date.available | 2026-07-07T02:54:08Z | |
| dc.description | A study of the quasi-particle excitations and spin fluctuations in the one-band Hubbard-model on the triangular lattice with nearest- and next-nearest-neighbor hopping is presented. Using the fluctuation-exchange-approximation (FLEX) results for the quasi-particle dispersion and life-time, the Fermi surface, and the static spin structure factor will be discussed for a wide range of dopings and as a function of the Coulomb correlation strength U. It is shown that the renormalization of the spin- and charge-dynamics is sensitive to the interplay between van Hove singularity-effects and the nesting, which is influenced by the next-nearest-neighbor hopping. For all dopings investigated, the energy-dependence of the quasi-particle life time is found to be of conventional Fermi-liquid nature. At intermediate correlation strength the static structure factor is strongly doping dependent, with a large commensurate peak at the K-point for 1.35 electrons per site and weak, incommensurate intensities occuring at lower electron densities. The relevance of this model to the recently discovered cobaltates Na_xCoO_2.yH_2O will be discussed. | |
| dc.description | REVTeX4, 5 pages, 6 figures; 3 labels added in fig.1, 2 sentences changed | |
| dc.identifier | https://arxiv.org/abs/cond-mat/0310244 | |
| dc.identifier | http://arxiv.org/abs/cond-mat/0310244 | |
| dc.identifier.uri | http://salesiana.dossiersoluciones.com/handle/123456789/22422 | |
| dc.subject | Strongly Correlated Electrons | |
| dc.title | Spin- and Charge Excitations of the Triangular Hubbard-Model: a FLEX-Study | |
| dc.type | text |