We study both numerically and analytically the possibility of using an
adiabatic passage control method to construct a Mach-Zehnder interferometer
(MZI) for Bose-Einstein condensates (BECs) in the time domain, in exact
one-to-one correspondence with the traditional optical MZI that involves two
beam splitters and two mirrors. The interference fringes one obtains from such
a minimum-disturbance set up clearly demonstrates that, fundamentally, an atom
laser is not monochromatic due to interatomic interactions. We also consider
how the amount of entanglement in the system correlates to the interference
fringes.Comment: 4 figures. Submitted for publicatio