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arXiv · 1610.07128

Linear optical quantum metrology with single photons --- Experimental errors, resource counting, and quantum Cramér-Rao bounds

Jonathan P. Olson·Keith R. Motes·Patrick M. Birchall·Nick M. Studer·Margarite LaBorde·Todd Moulder·Peter P. Rohde·Jonathan P. Dowling
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Abstract

Quantum number-path entanglement is a resource for super-sensitive quantum metrology and in particular provides for sub-shotnoise or even Heisenberg-limited sensitivity. However, such number-path entanglement has thought to have been resource intensive to create in the first place --- typically requiring either very strong nonlinearities, or nondeterministic preparation schemes with feed-forward, which are difficult to implement. Recently in [Phys. Rev. Lett. 114, 170802 (2015)] we showed that number-path entanglement from a BosonSampling inspired interferometer can be used to beat the shot-noise limit. In this manuscript we compare and contrast different interferometric schemes, discuss resource counting, calculate exact quantum Cramér-Rao bounds, and study details of experimental errors.

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Jonathan P. Olson, Keith R. Motes, Patrick M. Birchall, Nick M. Studer, Margarite LaBorde, Todd Moulder, Peter P. Rohde, Jonathan P. Dowling. 2017-03-07. Linear optical quantum metrology with single photons --- Experimental errors, resource counting, and quantum Cramér-Rao bounds. https://doi.org/10.1103/physreva.96.013810

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