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Quantum Metrology: Detection of weak forces using Schrodinger Cat resources

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

We investigate the utility of non classical states of simple harmonic oscillators (a superposition of coherent states) for sensitive force detection. We find that like squeezed states a superposition of coherent states allows the detection of 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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Kae Nemoto, W. J. Munro, G. J. Milburn, S. L. Braunstein. 2003-12-08. Quantum Metrology: Detection of weak forces using Schrodinger Cat resources. https://arxiv.org/abs/quant-ph/0312063

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