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arXiv:1708.01843 · Physical review. B./Physical review. B

Dynamics of the spin- 12 Heisenberg chain initialized in a domain-wall state

Grégoire Misguich, Kirone Mallick, P. L. Krapivsky

Published Nov 27, 2017• 86 citations
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Abstract

We study the dynamics of an isotropic spin-$\frac{1}{2}$ Heisenberg chain starting in a domain-wall initial condition where the spins are initially up on the left half-line and down on the right half-line. We focus on the long-time behavior of the magnetization profile. We perform extensive time-dependent density-matrix renormalization-group simulations (up to $t=350$) and find that the data are compatible with a diffusive behavior. Subleading corrections decay slowly blurring the emergence of the diffusive behavior. We also compare our results with two alternative scenarios: superdiffusive behavior and enhanced diffusion with a logarithmic correction. We finally discuss the evolution of the entanglement entropy.

DOI
10.1103/physrevb.96.195151

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