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arXiv · 1702.02697

Quantum limited measurement of space-time curvature with scaling beyond the conventional Heisenberg limit

Sebastian P. Kish·Timothy C. Ralph
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Abstract

We study the problem of estimating the phase shift due to the general relativistic time dilation in the interference of photons using a non-linear Mach-Zender interferometer setup. By introducing two non-linear Kerr materials, one in the bottom and one in the top arm, we can measure the non-linear phase $ϕ_{NL}$ produced by the space-time curvature and achieve a scaling of the standard deviation with photon number ($N$) of $1/N^β$ where $β> 1$, which exceeds the conventional Heisenberg limit of a linear interferometer ($1/N$). The non-linear phase shift is an effect that is amplified by the intensity of the probe field. In a regime of high number of photons, this effect can dominate over the linear phase shift.

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Sebastian P. Kish, Timothy C. Ralph. 2017-10-03. Quantum limited measurement of space-time curvature with scaling beyond the conventional Heisenberg limit. https://doi.org/10.1103/physreva.96.041801

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