Abstract
Strong one-dimensional (1D) lattices usually lead to unconnected two-dimensional gases. The long-range character of the dipole-dipole interactions leads to a scenario where nonoverlapping gases at different sites may interact significantly. We show that the excitations of nonoverlapping condensates in 1D optical lattices acquire a bandlike character, being collectively shared by different sites. In particular, the hybridization of the modes significantly enhances the rotonization of the excitations and may induce roton instability. We discuss the observability of this effect in ongoing experiments.
- Received 18 December 2008
DOI:https://doi.org/10.1103/PhysRevA.80.013611
©2009 American Physical Society