# Quantum imaging with sub-Poissonian light: challenges and perspectives in optical metrology

## TL;DR

This paper reviews quantum imaging techniques utilizing sub-Poissonian light, highlighting their potential to surpass classical measurement limits and discussing recent advances and future challenges in optical metrology.

## Contribution

It provides a comprehensive overview of quantum imaging methods based on non-classical light, emphasizing recent achievements and future perspectives in the field.

## Key findings

- Quantum correlations enable surpassing classical sensitivity limits.
- Recent experimental demonstrations show improved resolution with sub-Poissonian light.
- Potential applications include microscopy, biophotonics, and radiometry.

## Abstract

Non-classical correlations in optical beams offer the unprecedented opportunity of surpassing conventional limits of sensitivity and resolution in optical measurements and imaging, especially but not only, when a low photon flux down to the single photons are measured. We review the principles of quantum imaging and sensing techniques which exploit sub-Poissonian photon statistics and non-classical photon number correlation, presenting some state-of-the-art achievements in the field. These quantum photonics protocols have the potential to trigger major steps in many applications, such as microscopy and biophotonics and represent an important opportunity for a new deal in radiometry and photometry.