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arXiv · 0805.1402

QND measurements and state preparation in quantum gases by light detection

Igor B. Mekhov·Helmut Ritsch
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Abstract

We consider light scattering from ultracold atoms trapped in an optical lattice into a cavity. The measurement of photons leaking out the cavity provides a quantum nondemolition (QND) access to various atomic variables. Depending on the chosen geometry the time resolved light detection projects the atomic quantum state to various atom-number squeezed and Schroedinger cat states. Modifications of the atomic and light properties at a single quantum trajectory are demonstrated. The quantum structure of final states can be revealed by further observations of the same sample.

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Igor B. Mekhov, Helmut Ritsch. 2009-04-29. QND measurements and state preparation in quantum gases by light detection. https://doi.org/10.1103/physrevlett.102.020403

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