Enhancing information retrieval in quantum-optical critical systems via quantum measurement backaction
Abstract
Continuous monitoring of open quantum-optical systems offers a promising route towards quantum-enhanced estimation precision. In such continuous-measurement-based sensing protocols, the ultimate precision limit is dictated, through the quantum Cram\'er-Rao bound, by the global quantum Fisher information associated with the joint system-environment state. Reaching this limit with established continuous measurement techniques in quantum optics remains an outstanding challenge. Here we present a sensing protocol tailored for open quantum-optical sensors that exhibit dissipative criticality, enabling them to significantly narrow the gap to the ultimate precision limit. Our protocol leverages a previously unexplored interplay between the quantum criticality and the quantum measurement backaction inherent in continuous general-dyne detection. We identify a performance sweet spot, near which the ultimate precision limit can be efficiently approached. Our protocol establishes a new pathway towards quantum-enhanced precision in open quantum-optical setups and can be extended to other sensor designs featuring similar dissipative criticality.
Keywords
Cite
@article{arxiv.2511.22248,
title = {Enhancing information retrieval in quantum-optical critical systems via quantum measurement backaction},
author = {Cheng Zhang and Mauro Cirio and Xin-Qi Li and Pengfei Liang},
journal= {arXiv preprint arXiv:2511.22248},
year = {2025}
}
Comments
19 pages, 10 figures