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arXiv · 1201.6039

Weak value amplification in a shot-noise limited interferometer

Atsushi Nishizawa·Kouji Nakamura·Masa-Katsu Fujimoto
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Abstract

We study the weak-value amplification (WVA) in a phase measurement with an optical interferometer in which shot noise limits the sensitivity. We compute the signal and the shot noise including the full-order interaction terms of the WVA, and show that the shot-noise contribution to a phase shift in a pointer variable is always larger than the final variance of the pointer variable. This yields difference in estimating noise level up to a factor of 1.5. To clarify an advantage for practical uses of the WVA, we discuss signal-to-noise ratio and its optimization in the presence of the shot noise.

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Atsushi Nishizawa, Kouji Nakamura, Masa-Katsu Fujimoto. 2012-06-25. Weak value amplification in a shot-noise limited interferometer. https://doi.org/10.1103/physreva.85.062108

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