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arXiv · 1204.4851

Strategies for choosing path-entangled number states for optimal robust quantum optical metrology in the presence of loss

Kebei Jiang·Chase J. Brignac·Yi Weng·Moochan B. Kim·Hwang Lee·Jonathan P. Dowling
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Abstract

To acquire the best path-entangled photon Fock states for robust quantum optical metrology with parity detection, we calculate phase information from a lossy interferometer by using twin entangled Fock states. We show that (a) when loss is less than 50% twin entangled Fock states with large photon number difference give higher visibility while when loss is higher than 50% the ones with less photon number difference give higher visibility; (b) twin entangled Fock states with large photon number difference give sub-shot-noise limit sensitivity for phase detection in a lossy environment. This result provides a reference on what particular path-entangled Fock states are useful for real world metrology applications.

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Kebei Jiang, Chase J. Brignac, Yi Weng, Moochan B. Kim, Hwang Lee, Jonathan P. Dowling. 2012-04-22. Strategies for choosing path-entangled number states for optimal robust quantum optical metrology in the presence of loss. https://doi.org/10.1103/physreva.86.013826

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