2024/04/18 by Tommaso Roscilde, Roscilde, Tommaso, Filippo Caleca +5
Economics, Econometrics and Finance · Physics and Astronomy · #Cold Atom Physics and Bose-Einstein Condensates #Complex Systems and Time Series Analysis #FOS: Physical sciences #Quantum Physics (quant-ph) #Quantum many-body systems #Statistical Mechanics (cond-mat.stat-mech) #Strongly Correlated Electrons (cond-mat.str-el)
paper · pdf · doi:10.48550/arxiv.2404.12514
openalex publication_date 2024/04/18 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
Long-range spin-spin interactions are known to generate non-equilibrium dynamics which can squeeze the collective spin of a quantum spin ensemble in a scalable manner, leading to states whose metrologically useful entanglement grows with system size. Here we show theoretically that scalable squeezing can be produced in 2d U(1)-symmetric systems even by short-range interactions, i.e. interactions that at equilibrium do not lead to long-range order at finite temperatures, but rather to an extended, Berezhinski-Kosterlitz-Thouless (BKT) critical phase. If the initial state is a coherent spin state in the easy plane of interactions, whose energy corresponds to a thermal state in the critical BKT phase, the non-equilibrium dynamics exhibits critical slowing down, corresponding to a power-law decay of the collective magnetization in time. This slow decay protects scalable squeezing, whose scaling reveals in turn the decay exponent of the magnetization. Our results open the path to realizing massive entangled states of potential metrological interest in many relevant platforms of quantum simulation and information processing -- such as Mott insulators of ultracold atoms, or superconducting circuits -- characterized by short-range interactions in planar geometries.