Institute for Theoretical Physics Amsterdam and Delta Institute for Theoretical Physics, University of Amsterdam, Science Park 904, 1098 XH Amsterdam, Netherlands.
Département de Physique, Ecole Normale Supérieure, PSL Research University, CNRS, 24 rue Lhomond, 75005 Paris, France.
Phys Rev Lett. 2018 Dec 7;121(23):230602. doi: 10.1103/PhysRevLett.121.230602.
We identify a class of one-dimensional spin and fermionic lattice models that display diverging spin and charge diffusion constants, including several paradigmatic models of exactly solvable, strongly correlated many-body dynamics such as the isotropic Heisenberg spin chains, the Fermi-Hubbard model, and the t-J model at the integrable point. Using the hydrodynamic transport theory, we derive an analytic lower bound on the spin and charge diffusion constants by calculating the curvature of the corresponding Drude weights at half-filling, and demonstrate that for certain lattice models with isotropic interactions some of the Noether charges exhibit superdiffusive transport at finite temperature and half-filling.
我们确定了一类具有发散自旋和电荷扩散常数的一维自旋和费米子晶格模型，包括几个具有精确可解的强关联多体动力学的范例模型，例如各向同性海森堡自旋链、费米-哈伯德模型和可积点的 t-J 模型。我们使用流体力学输运理论，通过计算相应的 Drude 权重在半满时的曲率，从解析上推导出自旋和电荷扩散常数的下界，并证明对于具有各向同性相互作用的某些晶格模型，某些诺特定理电荷在有限温度和半满时表现出超扩散输运。
