QUANTUM DYNAMICS OF AN ATOMIC BOSE-EINSTEIN CONDENSATE IN A DOUBLE-WELL POTENTIAL

We consider the quantum dynamics of a neutral atom Bose-Einstein conde nsate in a double-well potential, including many-body hard-sphere inte ractions. Using a mean-field factorization we show that the coherent o scillations due to tunneling are suppressed when the number of atoms e xceeds a critical value. An exact quantum solution, in a two-mode appr oximation, shows that the mean-field solution is modulated by a quantu m collapse and revival sequence.