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arXiv · 2507.03780

Domain-wall melting and entanglement in free-fermion chains with a band structure

Viktor Eisler
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Abstract

We study the melting of a domain wall in free-fermion chains, where the periodic variation of the hopping amplitudes gives rise to a band structure. It is shown that the entanglement grows logarithmically in time, and the prefactor is proportional to the number of filled bands in the initial state. For a dimerized chain the particle density and current are found to have the same expressions as in the homogeneous case, up to a rescaling of the velocity. The universal contribution to the entropy profile is then doubled, while the non-universal part can be extracted numerically from block-Toeplitz matrices.

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BibTeXRIS

Viktor Eisler. 2025-07-04. Domain-wall melting and entanglement in free-fermion chains with a band structure. https://doi.org/10.21468/scipostphyscore.8.4.069

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