Interference of interacting matter waves - Gustavsson, Mattias; Haller, Elmar; Mark, Manfred; Danzl, Johann G; Hart, Russell; Daley, Andrew; Nägerl, Hanns (New Journal of Physics, 2010)
The phenomenon of matter-wave interference lies at the heart of quantum physics. It has been observed in various contexts in the limit of non-interacting particles as a single-particle effect. Here we observe and control matter-wave interference whose evolution is driven by interparticle interactions. In a multi-path matter-wave interferometer, the macroscopic manybody wave function of an interacting atomic Bose-Einstein condensate develops a regular interference pattern, allowing us to detect and directly visualize the effect of interaction-induced phase shifts. We demonstrate control over the phase evolution by inhibiting interaction-induced dephasing and by refocusing a dephased macroscopic matter wave in a spin-echo-type experiment. Our results show that interactions in a many-body system lead to a surprisingly coherent evolution, possibly enabling narrow-band and high-brightness matterwave interferometers based on atom lasers.
published
yes
Keywords: article