2024-09-02 ミュンヘン大学（LMU）
＜関連情報＞
- https://www.lmu.de/en/newsroom/news-overview/news/quantum-physics-describing-chaotic-systems.html
- https://www.nature.com/articles/s41567-024-02611-z
カオス量子系におけるゆらぎ流体力学の出現 Emergence of fluctuating hydrodynamics in chaotic quantum systems
Julian F. Wienand,Simon Karch,Alexander Impertro,Christian Schweizer,Ewan McCulloch,Romain Vasseur,Sarang Gopalakrishnan,Monika Aidelsburger & Immanuel Bloch
Nature Physics Published:12 August 2024
DOI:https://doi.org/10.1038/s41567-024-02611-z
Abstract
A fundamental principle of chaotic quantum dynamics is that local subsystems eventually approach a thermal equilibrium state. The corresponding timescales increase with subsystem size as equilibration is limited by the hydrodynamic build-up of fluctuations on extended length scales. We perform large-scale quantum simulations that monitor particle-number fluctuations in tunable ladders of hard-core bosons and explore how the build-up of fluctuations changes as the system crosses over from integrable to fully chaotic dynamics. Our results indicate that the growth of large-scale fluctuations in chaotic, far-from-equilibrium systems is quantitatively determined by equilibrium transport coefficients, in agreement with the predictions of fluctuating hydrodynamics. This emergent hydrodynamic behaviour of subsystem fluctuations provides a test of fluctuation–dissipation relations far from equilibrium and allows the accurate determination of equilibrium transport coefficients using far-from-equilibrium quantum dynamics.
