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Measurement of the Coherence of a Bose-Einstein Condensate



Edward W. Hagley, Lu Deng, M M. Kozuma, M Trippenbach, Y B. Band, M Edwards, M R. Doery, Paul S. Julienne, Kristian Helmerson, S L. Rolston, William D. Phillips


We study the coherence properties of a Bose-Einstein condensates using an interference technique. Two 100 ns optical standing wave pulses are applied to a condensate with a variable time delay between them. Each standing wave phase grating makes small copies of the condensate displaced in a momentum space. The quantum mechanical amplitudes of each copy interfere, depending on {Δ}t and on spatial phase variations across the condensate. We find that the behavior of a trapped BEC is consistent with a uniform spatial phase whereas a released BEC exhibits large phase variations across the condensate.
Physical Review Letters
No. 16


Bose-Einstein condensation, coherence length, diffraction, spatial coherence


Hagley, E. , Deng, L. , Kozuma, M. , Trippenbach, M. , Band, Y. , Edwards, M. , Doery, M. , Julienne, P. , Helmerson, K. , Rolston, S. and Phillips, W. (1999), Measurement of the Coherence of a Bose-Einstein Condensate, Physical Review Letters (Accessed February 28, 2024)
Created October 1, 1999, Updated October 22, 2018