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arXiv · 1810.13340

Ion-based nondestructive sensor for cavity photon numbers

Moonjoo Lee·Konstantin Friebe·Dario A. Fioretto·Klemens Schüppert·Florian R. Ong·David Plankensteiner·Valentin Torggler·Helmut Ritsch·Rainer Blatt·Tracy E. Northup
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Abstract

We dispersively couple a single trapped ion to an optical cavity to extract information about the cavity photon-number distribution in a nondestructive way. The photon-number-dependent AC-Stark shift experienced by the ion is measured via Ramsey spectroscopy. We use these measurements first to obtain the ion-cavity interaction strength. Next, we reconstruct the cavity photon-number distribution for coherent states and for a state with mixed thermal-coherent statistics, finding overlaps above 99% with the calibrated states.

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Moonjoo Lee, Konstantin Friebe, Dario A. Fioretto, Klemens Schüppert, Florian R. Ong, David Plankensteiner, Valentin Torggler, Helmut Ritsch, Rainer Blatt, Tracy E. Northup. 2018-10-31. Ion-based nondestructive sensor for cavity photon numbers. https://doi.org/10.1103/physrevlett.122.153603

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