Dynamic Critical Behavior of The Anisotropic Classical Heisenberg Antiferromagnet in Three Dimensions

Shan-Ho Tsai, Alex Bunker, D.P. Landau

Alex Bunker, Kun Chen, David Paul Landau

L.S. Lima, Antonio S. T. Pires, B. V. Costa

Anders W. Sandvik

We present results of extensive quantum Monte Carlo simulations of the three-dimensional $S\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}1/2$ Heisenberg antiferromagnet. Finite-size scaling of the spin stiffness and the sublattice magnetization gives the critical temperature ${T}_{\mathrm{c}}/J\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}0.946\ifmmode\pm\else\textpm\fi{}0.001$. The critical behavior is consistent with the classical 3D Heisenberg universality class, as expected. We discuss the general nature of the transition from quantum mechanical to classical (thermal) order parameter fluctuations at a continuous ${T}_{\mathrm{c}}>0$ phase transition.

Giammarco Fabiani, Johan H. Mentink

We investigate entanglement dynamics in the antiferromagnetic Heisenberg model in two dimensions following a spatially anisotropic quench of the exchange interactions. Opposed to established results in one dimension, the magnon quasiparticles show an initial growth of entanglement dynamics that does not depend on the system size and is governed by the oscillation period of the exchange interaction. This is much faster than the highest quasiparticle velocity, which we explain by the dominance of the intrinsic entanglement of short wavelength non-propagating magnon-pairs. Furthermore, by adopting the neural quantum states, we provide numerical evidence that this behavior survives even in the presence of strong magnon-magnon interactions, suggesting new avenues for manipulating entanglement dynamics in quantum materials.

J. Ricardo de Sousa, J. A. Plascak