A semi-classical limit for the many-body localization transition

Anushya Chandran; C. R. Laumann

doi:10.1103/physrevb.92.024301

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arXiv · 1501.01971

A semi-classical limit for the many-body localization transition

Anushya Chandran·C. R. Laumann

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Abstract

We introduce a semi-classical limit for many-body localization in the absence of global symmetries. Microscopically, this limit is realized by disordered Floquet circuits composed of Clifford gates. In $d=1$, the resulting dynamics are always many-body localized with a complete set of strictly local integrals of motion. In $d\geq 2$, the system realizes both localized and delocalized phases separated by a continuous transition in which ergodic puddles percolate. We argue that the phases are stable to deformations away from the semi-classical limit and estimate the resulting phase boundary. The Clifford circuit model is a distinct tractable limit from that of free fermions and suggests bounds on the critical exponents for the generic transition.

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Anushya Chandran, C. R. Laumann. 2015-01-08. A semi-classical limit for the many-body localization transition. https://doi.org/10.1103/physrevb.92.024301

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