Quasi-conserved quantities in the perturbed XXX spin chain

Savvas Malikis; Denis Kurlov; Vladimir Gritsev

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arXiv · 2007.01715

Quasi-conserved quantities in the perturbed XXX spin chain

Savvas Malikis·Denis Kurlov·Vladimir Gritsev

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Abstract

We consider the isotropic spin-1/2 Heisenberg spin chain weakly perturbed by a local translationally- and SU(2)-invariant perturbation. Starting from the local integrals of motion of the unperturbed model, we modify them in order to obtain quasi-conserved integrals of motion (charges) for the perturbed model. Such quasi-conserved quantities are believed to be responsible for the existence of the prethermalization phase at intermediate timescales. We find that for a sufficiently local perturbation only the first few integrals of motion can be promoted to the quasi-conserved charges, whereas higher-order integrals of motion do not survive.

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Savvas Malikis, Denis Kurlov, Vladimir Gritsev. 2020-12-09. Quasi-conserved quantities in the perturbed XXX spin chain. https://arxiv.org/abs/2007.01715

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