Ruelle-Pollicott resonances of diffusive U(1)-invariant qubit circuits

Duh, Urban (author), Žnidarič, Marko (author)

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.

• Language: English
• Keywords: open quantum systems, Floquet systems, quantum chaos, quantum spin chains, diffusion
• Work type: Article
• Typology: 1.01 - Original Scientific Article
• Organization: FMF - Faculty of Mathematics and Physics
• Publication status: Published
• Publication version: Version of Record
• Year: 2026
• Number of pages: 32 str.
• Numbering: Vol. 20, iss. 2, art. no. 061
• PID: 20.500.12556/RUL-182242
• UDC: 530.145
• ISSN on article: 2542-4653
• DOI: 10.21468/SciPostPhys.20.2.061
• COBISS.SI-ID: 276525827
• Publication date in RUL: 05.05.2026

Record is a part of a journal

• Title: SciPost physics
• Publisher: SciPost Foundation
• ISSN: 2542-4653
• COBISS.SI-ID: 526154521

Licences

• License: CC BY 4.0, Creative Commons Attribution 4.0 International
• Link: http://creativecommons.org/licenses/by/4.0/
• Description: This is the standard Creative Commons license that gives others maximum freedom to do what they want with the work as long as they credit the author.

Secondary language

• Language: Slovenian
• Keywords: odprti kvantni sistemi, Floquetovi sistemi, kvantni kaos, kvantne spinske verige, difuzija

Projects

• Funder: ARIS - Slovenian Research and Innovation Agency
• Project number: J1-4385
• Name: Kvantna večdelčna fizika in nehermitskost

• Funder: ARIS - Slovenian Research and Innovation Agency
• Project number: P1-0402
• Name: Matematična fizika