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arXiv · 0805.1817

Atom Chip Diffraction of Bose-Einstein Condensates: The Role of Inter-Atomic Interactions

T. E. Judd·R. G. Scott·T. M. Fromhold
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Abstract

We use supercomputer simulations to show that inter-atomic interactions can strongly affect the phase evolution of Bose-Einstein condensates that are diffracted from atom chips, thereby explaining recent experiments. Interactions broaden and depopulate non-central diffraction orders and so, counter-intuitively, they actually reduce the spatial width of the diffracted cloud. This means, more generally, that the experiments cannot be fully described by non-interacting theories and, consequently, interferometers that use many interacting atoms to enhance sensitivity require complex calibration. We identify device geometries required to approximate non-interacting behavior.

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T. E. Judd, R. G. Scott, T. M. Fromhold. 2008-11-18. Atom Chip Diffraction of Bose-Einstein Condensates: The Role of Inter-Atomic Interactions. https://doi.org/10.1103/physreva.78.053623

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