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Weak force detection with superposed coherent states

W. J. Munro·K. Nemoto·G. J. Milburn·S. L. Braunstein
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Abstract

We investigate the utility of non classical states of simple harmonic oscillators, particularly a superposition of coherent states, for sensitive force detection. We find that like squeezed states a superposition of coherent states allows displacement measurements at the Heisenberg limit. Entangling many superpositions of coherent states offers a significant advantage over a single mode superposition states with the same mean photon number.

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W. J. Munro, K. Nemoto, G. J. Milburn, S. L. Braunstein. 2002-06-17. Weak force detection with superposed coherent states. https://doi.org/10.1103/physreva.66.023819

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