Skip to main content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.


The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Quantum and Classical Dynamics of BEC in a Large-Period Optical Lattice



Ian B. Spielman, Johnny H. Huckans, Bruno Laburthe-Tolra, James V. Porto, William D. Phillips


We experimentally investigate diffraction of a ^u87 Rb Bose-Einstein Condensate from a 1D optical lattice. We use a range of lattice periods and timescales, including those beyond the Raman-Nath limit. We compare the results to quantum mechanical and classical simulations, with quantitative and qualitative agreement, respectively. The classical simulation predicts that the envelope of the time-evolving diffraction pattern is shaped by caustics: singularities in the phase space density of classical trajectories. This behavior becomes increasingly clear as the lattice period grows.
Physical Review A (Atomic, Molecular and Optical Physics)


Bose-Einstein Condensate, caustics, collapse and revival, matter wave diffraction, Raman-Nath
Created April 4, 2016, Updated February 19, 2017