Ruelle-Pollicott resonances of diffusive U(1)-invariant qubit circuits, by Urban Duh, Marko Žnidarič
Summarize this article with:
SciPost Physics Home Authoring Refereeing Submit a manuscript About Ruelle-Pollicott resonances of diffusive U(1)-invariant qubit circuits Urban Duh, Marko Žnidarič SciPost Phys. 20, 061 (2026) · published 26 February 2026 doi: 10.21468/SciPostPhys.20.2.061 pdf BiBTeX RIS Submissions/Reports Abstract We study Ruelle-Pollicott resonances of translationally invariant magnetization-conserving qubit circuits via the spectrum of the quasi-momentum-resolved truncated propagator of extensive observables. Diffusive transport of the conserved magnetization is reflected in the Gaussian quasi-momentum $k$ dependence of the leading eigenvalue (Ruelle-Pollicott resonance) of the truncated propagator for small $k$. This, in particular, allows us to extract the diffusion constant. For large $k$, the leading Ruelle-Pollicott resonance is not related to transport and governs the exponential decay of correlation functions. Additionally, we conjecture the existence of a continuum of eigenvalues below the leading diffusive resonance, which governs non-exponential decay, for instance, power-law hydrodynamic tails. We expect our conclusions to hold for generic systems with exactly one U(1) conserved quantity. × TY - JOURPB - SciPost FoundationDO - 10.21468/SciPostPhys.20.2.061TI - Ruelle-Pollicott resonances of diffusive U(1)-invariant qubit circuitsPY - 2026/02/26UR - https://scipost.org/SciPostPhys.20.2.061JF - SciPost PhysicsJA - SciPost Phys.VL - 20IS - 2SP - 061A1 - Duh, UrbanAU - Žnidarič, MarkoAB - We study Ruelle-Pollicott resonances of translationally invariant magnetization-conserving qubit circuits via the spectrum of the quasi-momentum-resolved truncated propagator of extensive observables. Diffusive transport of the conserved magnetization is reflected in the Gaussian quasi-momentum $k$ dependence of the leading eigenvalue (Ruelle-Pollicott resonance) of the truncated propagator for small $k$. This, in particular, allows us to extract the diffusion constant. For large $k$, the leading Ruelle-Pollicott resonance is not related to transport and governs the exponential decay of correlation functions. Additionally, we conjecture the existence of a continuum of eigenvalues below the leading diffusive resonance, which governs non-exponential decay, for instance, power-law hydrodynamic tails. We expect our conclusions to hold for generic systems with exactly one U(1) conserved quantity.ER - × @Article{10.21468/SciPostPhys.20.2.061, title={{Ruelle-Pollicott resonances of diffusive U(1)-invariant qubit circuits}}, author={Urban Duh and Marko Žnidarič}, journal={SciPost Phys.}, volume={20}, pages={061}, year={2026}, publisher={SciPost}, doi={10.21468/SciPostPhys.20.2.061}, url={https://scipost.org/10.21468/SciPostPhys.20.2.061},} Ontology / Topics See full Ontology or Topics database. Diffusive transport Open quantum systems Periodically-driven (Floquet) systems Quantum chaos Quantum spin chains Authors / Affiliation: mappings to Contributors and Organizations See all Organizations. 1 Urban Duh, 1 Marko Žnidarič 1 Univerza v Ljubljani / University of Ljubljana [UL] Funder for the research work leading to this publication Javna Agencija za Raziskovalno Dejavnost RS / Slovenian Research Agency [ARRS]