2008/02/29 by Guin-Dar Lin, G. -D. Lin, Wei Zhang +2 · 6 citations
Chemistry · Physics and Astronomy · #Cold Atom Physics and Bose-Einstein Condensates #Spectroscopy and Laser Applications #Strong Light-Matter Interactions #cond-mat.stat-mech #cond-mat.supr-con
paper · pdf · doi:10.1103/physreva.77.043626
published as Phys. Rev. A 77, 043626 (2008) · 12 pages, 13 figures; Revised version with new figures; Phys. Rev. A 77, 043626 (2008)
openalex publication_date 2008/04/23 · arxiv created 2008/05/21 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We discuss several possible experimental signatures of the Bose-Einstein condensation (BEC) transition for an ultracold Bose gas in an inhomogeneous optical lattice. Based on the commonly used time-of-flight imaging technique, we show that the momentum-space density profile in the first Brillouin zone, supplemented by the visibility of interference patterns, provides valuable information about the system. In particular, by crossing the BEC transition temperature, the appearance of a clear bimodal structure sets a qualitative and universal signature of this phase transition. Furthermore, the momentum distribution can also be applied to extract the condensate fraction, which may serve as a promising thermometer in such a system.