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arXiv · 0805.0296

Entangled Fock states for Robust Quantum Optical Metrology, Imaging, and Sensing

Sean D. Huver·Christoph F. Wildfeuer·Jonathan P. Dowling
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Abstract

We propose a class of path-entangled photon Fock states for robust quantum optical metrology, imaging, and sensing in the presence of loss. We model propagation loss with beam-splitters and derive a reduced density matrix formalism from which we examine how photon loss affects coherence. It is shown that particular entangled number states, which contain a special superposition of photons in both arms of a Mach-Zehnder interferometer, are resilient to environmental decoherence. We demonstrate an order of magnitude greater visibility with loss, than possible with N00N states. We also show that the effectiveness of a detection scheme is related to super-resolution visibility.

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Sean D. Huver, Christoph F. Wildfeuer, Jonathan P. Dowling. 2008-08-15. Entangled Fock states for Robust Quantum Optical Metrology, Imaging, and Sensing. https://doi.org/10.1103/physreva.78.063828

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