Hamburg 2009 – scientific programme

Parts | Days | Selection | Search | Downloads | Help

A: Fachverband Atomphysik

A 19: Ultracold atoms III: Manipulation and detection / Rydbergatoms (with Q)

A 19.4: Talk

Wednesday, March 4, 2009, 17:15–17:30, Audi-B

Quantum resolution limits for imaging Bose gases — •Antonio Negretti^1,2, Carsten Henkel³, and Klaus Molmer² — ¹Institut für Quanteninformationsverarbeitung, Universität Ulm, Albert-Einstein-Allee 11, D-89081 Ulm, Germany — ²Lundbeck Foundation Theoretical Center for Quantum System Research Department of Physics and Astronomy, University of Aarhus, DK-8000 Aarhus C, Denmark — ³Universität Potsdam, Institut für Physik und Astronomie, Karl-Liebknecht-Str. 24/25, D-14476 Potsdam, Germany

We present an analysis of the resolution limits for observables contained in the density profiles for an ultracold Bose gas of atoms. Within the Bogoliubov approximation we compute the density-density correlations by including both quantum and thermal fluctuations. These correlations provide a tool to construct the (approximate) joint counting statistics of atoms in an array of pixels covering the gas. As an example of the general theory, we derive the position uncertainty of a dark soliton in a quasi one dimensional Bose gas. The smallest uncertainty scales with the atomic background density, n, as n^−3/4, beating the classical shot noise limit. Intriguingly, the sensitivity is slightly improved when quantum fluctuations are included.