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Spectroscopy Using Quantum Logic



Piet Schmidt, Till P. Rosenband, C. Langer, Wayne M. Itano, James C. Bergquist, David J. Wineland


We have demonstrated experimentally a general technique for precision spectroscopy of atoms that lack suitable transitions for efficient laser cooling, internal state preparation, and detection. In our implementation with trapped atomic ions, an auxillary "logic" ion provides sympathetic laser cooling, state initialization, and detection for simultaneously trapped "spectroscopy" ion. Detection is achieved by applying a mapping operation on each ion, which results in a coherent transfer of the spectroscopy ion's internal state onto the logic ion, where it is then measured with high efficiency. Our experimental realization, which uses \Be as the logic ion, and \Al as the spectroscopy ion, indicates the feasibility of applying this technique to realize accurate optical clocks based on single ions.


atom trapping and cooling, quantum control, quantum entanglement, quantum information processing, quantum-state engineering, teleportation, trapped ions


Schmidt, P. , Rosenband, T. , Langer, C. , Itano, W. , Bergquist, J. and Wineland, D. (2005), Spectroscopy Using Quantum Logic, Science, [online], (Accessed June 16, 2024)


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Created July 29, 2005, Updated January 27, 2020