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arXiv · 2012.07488

Absence of superdiffusion in the quasiperiodic spin chain at weak integrability breaking

Marko Znidaric
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Abstract

There has been interest in the spin transport properties of the Aubry-Andre-Harper model at high temperatures under weak integrability breaking, in particular for small interactions or small fields. We present old unpublished and new results that show that the model is diffusive, meaning that the claimed superdiffusion [1,2] is a finite-size effect.

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Marko Znidaric. 2020-12-14. Absence of superdiffusion in the quasiperiodic spin chain at weak integrability breaking. https://doi.org/10.1103/physrevb.103.237101

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