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Optimal Frequency Measurements with Maximally Correlated States



John J. Bollinger, Wayne M. Itano, David J. Wineland, D J. Heinzen


We show how maximally correlated states of N two-level particles can be used in spectroscopy to yield a frequency uncertainty equal to (NT)-1, where T is the time of a single measurement. From the time-energy uncertainty relation we show that this is the best precision possible. We rephrase these results in the language of particle interferometry and obtain a state and detection operator which can be used to achieve a phase uncertainty exactly equal to the 1/N Heisenberg limit, where N is the number of particles used in the measurement.
Physical Review Letters


Bollinger, J. , Itano, W. , Wineland, D. and Heinzen, D. (1996), Optimal Frequency Measurements with Maximally Correlated States, Physical Review Letters, [online], (Accessed May 27, 2024)


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Created December 1, 1996, Updated February 19, 2017