Charge degrees in the quarter-filled checkerboard lattice

F. Pollmann; J. J. Betouras; E. Runge; P. Fulde

doi:10.1016/j.jmmm.2006.10.348

paper

Charge degrees in the quarter-filled checkerboard lattice

arXiv:cond-mat/0609122 · doi:10.1016/j.jmmm.2006.10.348

Abstract

For a systematic study of charge degrees of freedom in lattices with geometric frustration, we consider spinless fermions on the checkerboard lattice with nearest-neighbor hopping $t$ and nearest-neighbor repulsion $V$ at quarter-filling. An effective Hamiltonian for the limit $∣ t ∣ ≪ V$ is given to lowest non-vanishing order by the ring exchange ( $\sim t^{3} / V^{2}$ ). We show that the system can equivalently be described by hard-core bosons and map the model to a confining U(1) lattice gauge theory.

Proceedings of ICM2006