Decay of spin helices in XXZ quantum spin chains with single-ion anisotropy
Abstract
Long-lived spin-helix states facilitate the study of non-equilibrium dynamics in quantum magnets. We consider the decay of transverse spin-helices in antiferromagnetic spin- XXZ chains with single-ion anisostropy. The spin-helix decay is observable in the time evolution of the local magnetization that we calculate numerically for the system in the thermodynamic limit using infinite time-evolving block decimation simulations. Although the single-ion anisotropy prevents helix states from being eigenstates of the Hamiltonian, they still can be long-lived for appropriately chosen wave numbers. In case of an easy-axis exchange anisotropy the single-ion anisotropy may even stabilize the helices. Within a spin-wave approximation, we obtain a condition giving an estimate for the most stable wave number that agrees qualitatively with our numerical results.
Cite
@article{arxiv.2512.08421,
title = {Decay of spin helices in XXZ quantum spin chains with single-ion anisotropy},
author = {Florian Lange and Frank Göhmann and Gerhard Wellein and Holger Fehske},
journal= {arXiv preprint arXiv:2512.08421},
year = {2026}
}
Comments
revised version, 8 pages, 8 figures