Quantum sensing with critical systems: impact of symmetry, imperfections, and decoherence
Abstract
Entangled many-body states enable high-precision quantum sensing beyond the standard quantum limit. We develop interferometric sensing protocols based on quantum critical wavefunctions and compare their performance with Greenberger-Horne-Zeilinger (GHZ) and spin-squeezed states. Building on the idea of symmetries as a metrological resource, we introduce a symmetry-based algorithm to identify optimal measurement strategies. We illustrate this algorithm both for magnetic systems with internal symmetries and Rydberg-atom arrays with spatial symmetries. We study the robustness of criticality for quantum sensing under non-unitary deformations, symmetry-preserving and symmetry-breaking decoherence, and qubit loss -- identifying regimes where critical systems outperform GHZ states and showing that non-unitary deformation can even enhance sensing precision. Combined with recent results on log-depth preparation of critical wavefunctions, interferometric sensing in this setting appears increasingly promising.
Keywords
Cite
@article{arxiv.2601.04364,
title = {Quantum sensing with critical systems: impact of symmetry, imperfections, and decoherence},
author = {Yinan Chen and Sara Murciano and Pablo Sala and Jason Alicea},
journal= {arXiv preprint arXiv:2601.04364},
year = {2026}
}