Quantum limits for resolving Gaussian sources
- URL: http://arxiv.org/abs/2205.04258v1
- Date: Mon, 9 May 2022 13:18:57 GMT
- Title: Quantum limits for resolving Gaussian sources
- Authors: Giacomo Sorelli, Manuel Gessner, Mattia Walschaers, and Nicolas Treps
- Abstract summary: We determine the quantum Cram'er-Rao bound for the estimation of the separation between two point sources in arbitrary Gaussian states.
In practical scenarios, we find coherent states of the sources to achieve quantum optimal resolution.
- Score: 0.0
- License: http://creativecommons.org/licenses/by/4.0/
- Abstract: We determine analytically the quantum Cram\'er-Rao bound for the estimation
of the separation between two point sources in arbitrary Gaussian states. Our
analytical expression is valid for arbitrary sources brightness, and it allows
to determine how different resources, such as mutual coherence (induced by
thermal correlations or displacement) or squeezing affect the scaling of the
ultimate resolution limit with the mean number of emitted photons. In practical
scenarios, we find coherent states of the sources to achieve quantum optimal
resolution.
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