2010/07/13 by C. F. Ockeloen, A. F. Tauschinsky, R. J. C. Spreeuw +1
Physics and Astronomy · #physics.atom-ph #cond-mat.quant-gas
paper · pdf · doi:10.1103/physreva.82.061606
published as Phys. Rev. A 82, 061606 (2010) · 4 pages, 3 figures
arxiv created 2010/07/13 · arxiv updated 2010/12/17
We demonstrate improved detection of small trapped atomic ensembles through advanced post-processing and optimal analysis of absorption images. A fringe removal algorithm reduces imaging noise to the fundamental photon-shot-noise level and proves beneficial even in the absence of fringes. A maximum-likelihood estimator is then derived for optimal atom-number estimation and is applied to real experimental data to measure the population differences and intrinsic atom shot-noise between spatially separated ensembles each comprising between 10 and 2000 atoms. The combined techniques improve our signal-to-noise by a factor of 3, to a minimum resolvable population difference of 17 atoms, close to our ultimate detection limit.