This project investigates the role of nonclassical states of light in quantum optics and their applications in quantum technologies. While coherent states and their mixtures can be explained classically, nonclassical states are essential for tasks in quantum computing, communication, and metrology. However, many quantum applications rely on incomplete measurement data, which may allow classical reproduction of nonclassical statistics. Building on recent results, we will study conditions under which nonclassicality remains preserved, develop a method to quantify it, and link it to quantum Fisher information—a key resource in metrology.

A central goal is to apply these findings to quantum metrology beyond its standard scope. We will extend the traditional quantum Cramér-Rao framework by treating the quantum channel (e.g., turbulent atmosphere) as part of detection, enabling estimation of detector and channel parameters. This dual optimization over quantum states, measurements, and channels addresses a critical challenge in quantum information theory.

We will develop methods to estimate parameters of the probability distribution of transmittance (PDT), the main characteristic of quantum atmospheric channels, using models proposed by the applicant. Additionally, we aim to adapt superresolution imaging techniques to atmospheric conditions, where light sources and detectors are separated by turbulent layers.

The project will thus advance both the fundamental understanding of nonclassicality and its practical applications in challenging real-world environments.