Absence of localization in interacting spin chains with a discrete symmetry

Benedikt Kloss; Jad C. Halimeh; Achilleas Lazarides; Yevgeny Bar Lev

doi:10.1038/s41467-023-39468-4

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arXiv · 2208.13793

Absence of localization in interacting spin chains with a discrete symmetry

Benedikt Kloss·Jad C. Halimeh·Achilleas Lazarides·Yevgeny Bar Lev

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Abstract

We prove that spin chains symmetric under a combination of mirror and spin-flip symmetries and with a nondegenerate spectrum show finite spin transport at zero total magnetization and infinite temperature. We demonstrate this numerically using two prominent examples: the Stark many-body localization system and the symmetrized many-body localization system. We provide evidence of delocalization at all energy densities and show that the delocalization mechanism is robust to breaking the symmetry. We use our results to construct two localized systems which, when coupled, delocalize each other.

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Benedikt Kloss, Jad C. Halimeh, Achilleas Lazarides, Yevgeny Bar Lev. 2022-08-29. Absence of localization in interacting spin chains with a discrete symmetry. https://doi.org/10.1038/s41467-023-39468-4

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