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Measurement of the Coherence of a Bose-Einstein Condensate
Published
Author(s)
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
Abstract
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.
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 October 9, 2025)