Ultrafast dynamics of entanglement in Heisenberg antiferromagnets

G. Fabiani; J. H. Mentink

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arXiv · 1912.10845

Ultrafast dynamics of entanglement in Heisenberg antiferromagnets

G. Fabiani·J. H. Mentink

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Abstract

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. We ascribe this to the dominance of the intrinsic entanglement of short wavelength non-propagating magnon-pairs, which also leads to a competition between area-law and volume-law contribution in the entanglement dynamics. Furthermore, by adopting the neural-network 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.

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G. Fabiani, J. H. Mentink. 2019-12-23. Ultrafast dynamics of entanglement in Heisenberg antiferromagnets. https://arxiv.org/abs/1912.10845

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