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DOE OSTI · 21413467

Parameter Estimation with Entangled Photons Produced by Parametric Down-Conversion

Cable, Hugo·Durkin, Gabriel A
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Abstract

We explore the advantages offered by twin light beams produced in parametric down-conversion for precision measurement. The symmetry of these bipartite quantum states, even under losses, suggests that monitoring correlations between the divergent beams permits a high-precision inference of any symmetry-breaking effect, e.g., fiber birefringence. We show that the quantity of entanglement is not the key feature for such an instrument. In a lossless setting, scaling of precision at the ultimate ''Heisenberg'' limit is possible with photon counting alone. Even as photon losses approach 100% the precision is shot-noise limited, and we identify the crossover point between quantum and classical precision as a function of detected flux. The predicted hypersensitivity is demonstrated with a Bayesian simulation.

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71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICSACCURACYBEAMSBIREFRINGENCEBOSONSCONVERSIONELECTROMAGNETIC RADIATIONELEMENTARY PARTICLESFIBERSMASSLESS PARTICLESMONITORINGPHOTON BEAMSPHOTONSQUANTUM ENTANGLEMENTRADIATIONSREFRACTIONSCALINGSIMULATIONSYMMETRY BREAKINGVISIBLE RADIATION

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Cable, Hugo, Durkin, Gabriel A. 2010-07-02. Parameter Estimation with Entangled Photons Produced by Parametric Down-Conversion. https://doi.org/10.1103/physrevlett.105.013603

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