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arXiv · 1803.07479

Hydrodynamical phase transition for domain-wall melting in the XY chain

Viktor Eisler·Florian Maislinger
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Abstract

We study the melting of a domain wall, prepared as a certain low-energy excitation above the ferromagnetic ground state of the XY chain. In a well defined parameter regime the time-evolved magnetization profile develops sharp kink-like structures in the bulk, showing features of a phase transition in the hydrodynamic scaling limit. The transition is of purely dynamical nature and can be attributed to the appearance of a negative effective mass term in the dispersion. The signatures are also clearly visible in the entanglement profile measured along the front region, which can be obtained by covariance-matrix methods despite the state being non-Gaussian.

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BibTeXRIS

Viktor Eisler, Florian Maislinger. 2018-03-20. Hydrodynamical phase transition for domain-wall melting in the XY chain. https://doi.org/10.1103/physrevb.98.161117

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