The usability of the optical parametric amplification of light for high-angular-resolution imaging and fast astrometry

TL;DR

This paper explores the potential of optical parametric amplification (OPA) to surpass the diffraction limit in high-angular-resolution imaging, proposing an updated scheme and analyzing its efficiency for astrophysical applications.

Contribution

The authors present an improved OPA-based scheme and a more accurate model predicting noise effects, demonstrating potential gains in resolution and source localization over classical optics.

Findings

OPA can increase angular resolution for extended sources.

OPA improves localization accuracy of distant point sources.

Noise in OPA systems forms light speckles due to interference.

Abstract

High-angular-resolution imaging is crucial for many applications in modern astronomy and astrophysics. The fundamental diffraction limit constrains the resolving power of both ground-based and spaceborne telescopes. The recent idea of a quantum telescope based on the optical parametric amplification (OPA) of light aims to bypass this limit for the imaging of extended sources by an order of magnitude or more. We present an updated scheme of an OPA-based device and a more accurate model of the signal amplification by such a device. The semiclassical model that we present predicts that the noise in such a system will form so-called light speckles as a result of light interference in the optical path. Based on this model, we analysed the efficiency of OPA in increasing the angular resolution of the imaging of extended targets and the precise localization of a distant point source. According to our new model, OPA offers a gain in resolved imaging in comparison to classical optics. For a given time-span, we found that OPA can be more efficient in localizing a single distant point source than classical telescopes.