  We investigate dynamic properties of bouncing and penetration in colliding
binary and ternary Bose-Einstein condensates comprised of different Zeeman or
hyperfine states of 87Rb. Through the application of magnetic field gradient
pulses, two- or three-component condensates in an optical trap are spatially
separated and then made to collide. The subsequent evolutions are classified
into two categories: repeated bouncing motion and mutual penetration after
damped bounces. We experimentally observed mutual penetration for immiscible
condensates, bouncing between miscible condensates, and domain formation for
miscible condensates. From numerical simulations of the Gross-Pitaevskii
equation, we find that the penetration time can be tuned by slightly changing
the atomic interaction strengths.
