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arXiv · 2104.14393

Enhanced weak-value amplification via photon recycling

Courtney Krafczyk·Andrew N. Jordan·Michael E. Goggin·Paul G. Kwiat
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Abstract

In a quantum-noise limited system, weak-value amplification using post-selection normally does not produce more sensitive measurements than standard methods for ideal detectors: the increased weak value is compensated by the reduced power due to the small post-selection probability. Here we experimentally demonstrate recycled weak-value measurements using a pulsed light source and optical switch to enable nearly deterministic weak-value amplification of a mirror tilt. Using photon counting detectors, we demonstrate a signal improvement by a factor of $4.4 \pm 0.2$ and a signal-to-noise ratio improvement of $2.10 \pm 0.06$, compared to a single-pass weak-value experiment, and also compared to a conventional direct measurement of the tilt. The signal-to-noise ratio improvement could reach around 6 for the parameters of this experiment, assuming lower loss elements.

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Courtney Krafczyk, Andrew N. Jordan, Michael E. Goggin, Paul G. Kwiat. 2021-04-29. Enhanced weak-value amplification via photon recycling. https://doi.org/10.1103/physrevlett.126.220801

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