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Title: Observing the Formation of Long-Range Order during Bose-Einstein Condensation

Abstract

We have experimentally investigated the formation of off-diagonal long-range order in a gas of ultracold atoms. A magnetically trapped atomic cloud prepared in a highly nonequilibrium state thermalizes and thereby crosses the Bose-Einstein condensation phase transition. The evolution of phase coherence between different regions of the sample is constantly monitored and information on the spatial first-order correlation function is obtained. We observe the growth of the spatial coherence and the formation of long-range order in real time and compare it to the growth of the atomic density. Moreover, we study the evolution of the momentum distribution during the nonequilibrium formation of the condensate.

Authors:
; ; ; ; ;  [1]
  1. Institute for Quantum Electronics, ETH Zuerich, 8093 Zurich (Switzerland)
Publication Date:
OSTI Identifier:
20957691
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review Letters; Journal Volume: 98; Journal Issue: 9; Other Information: DOI: 10.1103/PhysRevLett.98.090402; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; BOSE-EINSTEIN CONDENSATION; CORRELATION FUNCTIONS; EVOLUTION; PHASE TRANSFORMATIONS; RADIOACTIVE CLOUDS; TRAPPING

Citation Formats

Ritter, Stephan, Oettl, Anton, Donner, Tobias, Bourdel, Thomas, Koehl, Michael, and Esslinger, Tilman. Observing the Formation of Long-Range Order during Bose-Einstein Condensation. United States: N. p., 2007. Web. doi:10.1103/PHYSREVLETT.98.090402.
Ritter, Stephan, Oettl, Anton, Donner, Tobias, Bourdel, Thomas, Koehl, Michael, & Esslinger, Tilman. Observing the Formation of Long-Range Order during Bose-Einstein Condensation. United States. doi:10.1103/PHYSREVLETT.98.090402.
Ritter, Stephan, Oettl, Anton, Donner, Tobias, Bourdel, Thomas, Koehl, Michael, and Esslinger, Tilman. Fri . "Observing the Formation of Long-Range Order during Bose-Einstein Condensation". United States. doi:10.1103/PHYSREVLETT.98.090402.
@article{osti_20957691,
title = {Observing the Formation of Long-Range Order during Bose-Einstein Condensation},
author = {Ritter, Stephan and Oettl, Anton and Donner, Tobias and Bourdel, Thomas and Koehl, Michael and Esslinger, Tilman},
abstractNote = {We have experimentally investigated the formation of off-diagonal long-range order in a gas of ultracold atoms. A magnetically trapped atomic cloud prepared in a highly nonequilibrium state thermalizes and thereby crosses the Bose-Einstein condensation phase transition. The evolution of phase coherence between different regions of the sample is constantly monitored and information on the spatial first-order correlation function is obtained. We observe the growth of the spatial coherence and the formation of long-range order in real time and compare it to the growth of the atomic density. Moreover, we study the evolution of the momentum distribution during the nonequilibrium formation of the condensate.},
doi = {10.1103/PHYSREVLETT.98.090402},
journal = {Physical Review Letters},
number = 9,
volume = 98,
place = {United States},
year = {Fri Mar 02 00:00:00 EST 2007},
month = {Fri Mar 02 00:00:00 EST 2007}
}
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