1210.7696 (Zhihao Xu et al.)

Fractional topological states of dipolar fermions in one-dimensional
optical superlattices    [PDF]

Zhihao Xu, Linhu Li, Shu Chen

We study properties of dipolar fermions trapped in the one-dimensional bichromatic optical lattices and show the existence of fractional topological states in the presence of strong dipole-dipole interactions. We find some interesting connections between fractional topological states in one-dimensional superlattices and the fractional quantum Hall states: (i) the one-dimensional fractional topological states for systems at filling factor $\nu=1/p$ have $p$-fold degeneracy, (ii) the total Chern number of $p$-fold degenerate states is a nonzero integer, (iii) the quasihole excitations fulfill the same counting rule as that of fractional quantum Hall states. Despite of similarities of these nontrivial topological features, the existence of crystalline order in the one-dimensional system distinguishes it from the fractional quantum Hall state. The possible experimental realization in cold atomic systems offers a new platform for the study of fractional topological phases in one-dimensional superlattice systems.

View original: http://arxiv.org/abs/1210.7696