Superfluidity and stability of a Bose-Einstein condensate with periodically modulated interatomic interaction

Shao-Liang Zhang, Zheng-Wei Zhou, Biao Wu
2013 Physical Review A. Atomic, Molecular, and Optical Physics  
We study theoretically the superfluidity and stability of a Bose-Einstein condensate (BEC) whose interatomic scattering length is periodically modulated with optical Feshbach resonance. Our numerical study finds that the properties of this periodic BEC are strongly influenced by the modulation strength. When the modulation strength is small, only the Bloch waves close to the Brillouin zone edge suffer both Landau and dynamical instabilities. When the modulation strength is strong enough, all
more » ... ch waves become dynamically unstable. In other words, the periodic BEC loses its superfluidity completely.
doi:10.1103/physreva.87.013633 fatcat:rs6f54xtzrbh5jldal7abyexz4