Physics – Condensed Matter – Strongly Correlated Electrons
Scientific paper
2008-05-08
J. Magn. Magn. Mater. 310 (2007) 1331-1333
Physics
Condensed Matter
Strongly Correlated Electrons
2 pages including 2 figures, uses elsart style files; (proceedings of ICM 2006)
Scientific paper
10.1016/j.jmmm.2006.10.357
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 $\mu$. 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 $\mu$ is varied adiabatically at finite temperature.
Honecker Andreas
Richter Jadwiga
No associations
LandOfFree
Enhanced low-temperature entropy and flat-band ferromagnetism in the t-J model on the sawtooth lattice 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 Enhanced low-temperature entropy and flat-band ferromagnetism in the t-J model on the sawtooth lattice, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Enhanced low-temperature entropy and flat-band ferromagnetism in the t-J model on the sawtooth lattice will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-52929