2020/07/31 by Zhi-Cheng Yang, Stuart Nicholls, Meng Cheng · 2 citations
Physics and Astronomy · #Condensed matter physics #Floquet theory #Nonlinear system #Physics #Physics of Superconductivity and Magnetism #Quantum many-body systems #Quantum mechanics #Quantum, superfluid, helium dynamics #Spin (aerodynamics) #Statistical physics #cond-mat.dis-nn #cond-mat.stat-mech #cond-mat.str-el #quant-ph
paper · pdf · doi:10.1103/physrevb.102.214205
published in Physical review. B./Physical review. B 102(21) (American Physical Society) · updated to accepted version
arxiv created 2020/12/01 · openalex publication_date 2020/12/14 · arxiv updated 2020/12/15 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/06
We explore thermalization and quantum dynamics in a one-dimensional disordered SU(2)-symmetric Floquet model, where a many-body localized phase is prohibited by the non-Abelian symmetry. Despite the absence of localization, we find an extended nonergodic regime at strong disorder where the system exhibits nonthermal behaviors. In the strong disorder regime, the level spacing statistics exhibit neither a Wigner-Dyson nor a Poisson distribution, and the spectral form factor does not show a linear-in-time growth at early times characteristic of random matrix theory. The average entanglement entropy of the Floquet eigenstates is subthermal, although violating an area-law scaling with system sizes. We further compute the expectation value of local observables and find strong deviations from the eigenstate thermalization hypothesis. The infinite-temperature spin autocorrelation function decays at long times as t^\ensuremath-\ensuremathβ with \ensuremathβ<0.5, indicating subdiffusive transport at strong disorders.