Directed selective-tunneling of bosons with periodically modulated interaction

• The Floquet solutions in a modulating triple-well are obtained analytically.
• The directed selective-tunneling effect of a single atom is demonstrated.
• We present a manipulation scheme for separating a single atom from N bosons.

We study the tunneling dynamics of bosons with periodically modulated interaction held in a triple-well potential. In high-frequency approximation, we derive a set of reduced coupled equations and the corresponding Floquet solutions are obtained. Based on the analytical results and their numerical correspondence, the directed selective-tunneling effect of a single atom is demonstrated when all bosons are prepared in middle well initially. A scheme for separating a single atom from N bosons is presented, in which the atom can be trapped in right or left well by adjusting the modulation strength.