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Nonlinear Optics

Nonlinearity enhanced Fisher information for two-point super-resolution

S. A. Wadood, Shaurya Aarav, Jason W. Fleischer

Published Jan 1, 2023• 0 citations
Publisher

Abstract

We show that a nonlinear phase plate greatly increases the Fisher information for estimating the separation between two point sources. Nonlinearity enables resolution beyond the quantum limit from linear theory.
DOI
10.1364/nlo.2023.m3a.1

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The resolution of separation of two elementary signals forming a partially coherent superposition, defined by quantum Fisher information and normalized with respect to detection probabilities, is always limited by the resolution of incoherent mixtures. However, when the partially coherent superpositions are prepared in a controlled way, the precision can be enhanced by up to several orders of magnitude above this limit. Coherence also allows the sorting of information about various parameters into distinct channels as demonstrated by the parameter of separation linked with the anti-phase superposition and the centroid position linked with the in-phase superposition.
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