Enhanced low-temperature entropy and flat-band ferromagnetism in the t-J model on the sawtooth lattice
| dc.creator | Honecker, A. | |
| dc.creator | Richter, J. | |
| dc.date | 2008-05-08 | |
| dc.date.accessioned | 2026-07-07T09:37:44Z | |
| dc.date.available | 2026-07-07T09:37:44Z | |
| dc.description | Using the example of the sawtooth chain, we argue that the t-J model shares important features with the Hubbard model on highly frustrated lattices. The lowest single-fermion band is completely flat (for a specific choice of the hopping parameters $t_{i,j}$ in the case of the sawtooth chain), giving rise to single-particle excitations which can be localized in real space. These localized excitations do not interact for sufficient spatial separations such that exact many-electron states can also be constructed. Furthermore, all these excitations acquire zero energy for a suitable choice of the chemical potential $μ$. This leads to: (i) a jump in the particle density at zero temperature, (ii) a finite zero-temperature entropy, (iii) a ferromagnetic ground state with a charge gap when the flat band is fully occupied and (iv) unusually large temperature variations when $μ$ is varied adiabatically at finite temperature. | |
| dc.description | 2 pages including 2 figures, uses elsart style files; (proceedings of ICM 2006) | |
| dc.identifier | https://arxiv.org/abs/0805.1151 | |
| dc.identifier | http://arxiv.org/abs/0805.1151 | |
| dc.identifier | J. Magn. Magn. Mater. 310 (2007) 1331-1333 | |
| dc.identifier | doi:10.1016/j.jmmm.2006.10.357 | |
| dc.identifier.uri | http://salesiana.dossiersoluciones.com/handle/123456789/160565 | |
| dc.subject | Strongly Correlated Electrons | |
| dc.title | Enhanced low-temperature entropy and flat-band ferromagnetism in the t-J model on the sawtooth lattice | |
| dc.type | text |