Floquet engineering of correlated tunneling in the Bose-Hubbard model   with ultracold atoms
  We report on the experimental implementation of tunable occupation-dependent tunneling in a Bose-Hubbard system of ultracold atoms via time-periodic modulation of the on-site interaction energy. The tunneling rate is inferred from a time-resolved measurement of the lattice site occupation after a quantum quench. We demonstrate coherent control of the tunneling dynamics in the correlated many-body system, including full suppression of tunneling as predicted within the framework of Floquet theory. We find that the tunneling rate explicitly depends on the atom number difference in neighboring lattice sites. Our results may open up ways to realize artificial gauge fields that feature density dependence with ultracold atoms. 
Florian Meinert, Manfred J. Mark, Katharina Lauber, Andrew J. Daley,   Hanns-Christoph N\"agerl
cond-mat.quant-gas