English

Anisotropic Landau-Lifshitz Model in Discrete Space-Time

Statistical Mechanics 2026-01-09 v4

Abstract

We construct an integrable lattice model of classical interacting spins in discrete space-time, representing a discrete-time analogue of the lattice Landau-Lifshitz ferromagnet with uniaxial anisotropy. As an application we use this explicit discrete symplectic integration scheme to compute the spin Drude weight and diffusion constant as functions of anisotropy and chemical potential. We demonstrate qualitatively different behavior in the easy-axis and the easy-plane regimes in the non-magnetized sector. Upon approaching the isotropic point we also find an algebraic divergence of the diffusion constant, signaling a crossover to spin superdiffusion.

Keywords

Cite

@article{arxiv.2104.13863,
  title  = {Anisotropic Landau-Lifshitz Model in Discrete Space-Time},
  author = {Žiga Krajnik and Enej Ilievski and Tomaž Prosen and Vincent Pasquier},
  journal= {arXiv preprint arXiv:2104.13863},
  year   = {2026}
}

Comments

20 pages, 9 figures; V2: typos corrected, a few DOIs added; V3: mistake in Eq. (2.20) corrected, V4: Corrected typo in Eq. (2.43) - primes in (2, 2) matrix element swapped