arXiv:1401.5907 · Physical Review A
Tuning the quantum phase transition of bosons in optical lattices via periodic modulation of the s -wave scattering length
Tao Wang, Xue‐Feng Zhang, F. E. A. dos Santos, Sebastian Eggert, Axel Pelster
Abstract
We consider interacting bosons in a two-dimensional square and a three-dimensional cubic optical lattice with a periodic modulation of the $s$-wave scattering length. At first we map the underlying periodically driven Bose-Hubbard model for large enough driving frequencies approximately to an effective time-independent Hamiltonian with a conditional hopping. Combining different analytical approaches with quantum Monte Carlo simulations then reveals that the superfluid--Mott-insulator quantum phase transition still exists despite the periodic driving and that the location of the quantum phase boundary turns out to depend quite sensitively on the driving amplitude. A more detailed quantitative analysis shows that the effect of driving can even be described within the usual Bose-Hubbard model provided that the hopping is rescaled appropriately with the driving amplitude.