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arXiv · 1408.1266

Generation and detection of a sub-Poissonian atom number distribution in a one-dimensional optical lattice

J. -B. Béguin·E. Bookjans·S. L. Christensen·H. L. Sørensen·J. H. Müller·J. Appel·E. S. Polzik
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Abstract

We demonstrate preparation and detection of an atom number distribution in a one-dimensional atomic lattice with the variance $-14$ dB below the Poissonian noise level. A mesoscopic ensemble containing a few thousand atoms is trapped in the evanescent field of a nanofiber. The atom number is measured through dual-color homodyne interferometry with a pW-power shot noise limited probe. Strong coupling of the evanescent probe guided by the nanofiber allows for a real-time measurement with a precision of $\pm 8$ atoms on an ensemble of some $10^3$ atoms in a one-dimensional trap. The method is very well suited for generating collective atomic entangled or spin-squeezed states via a quantum non-demolition measurement as well as for tomography of exotic atomic states in a one-dimensional lattice.

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J. -B. Béguin, E. Bookjans, S. L. Christensen, H. L. Sørensen, J. H. Müller, J. Appel, E. S. Polzik. 2014-10-15. Generation and detection of a sub-Poissonian atom number distribution in a one-dimensional optical lattice. https://doi.org/10.1103/physrevlett.113.263603

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