Tunneling resonances and entanglement dynamics of ultracold bosons in a tilted two-well potential*

We study the quantum sloshing of ultracold bosons in a tilted double-well potential via exact diagonalization of the two-mode Bose-Hubbard Hamiltonian. Tunneling is extremely sensitive to a small potential difference between wells, or tilt. However, when the barrier is high, atom-atom interactions can compensate the tilt and produce a tunneling resonance [1, 2].~ At resonance, tunneling times on the order of 10-100 ms are possible. Furthermore, tunneling resonances constitute a dynamic scheme for creating robust few-atom entangled states in the presence of many bosons. \newline [1] D. R. Dounas-Frazer and L. D. Carr, e-print: quant-ph/0610166 (2006). \newline [2] D. R. Dounas-Frazer, A. M. Hermundstad, and L. D. Carr, e-print: quant-ph/0609119 (2006).