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arXiv · 1801.03204

Many-Body Localization in a finite-range Sachdev-Ye-Kitaev model

Antonio M. García-García·Masaki Tezuka
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Abstract

We study the level statistics of a generalized Sachdev-Ye-Kitaev (SYK) model with two-body and one-body random interactions of finite range by exact diagonalization. Tuning the range of the one-body term, while keeping the two-body interaction sufficiently long-ranged, does not alter substantially the spectral correlations, which are still given by the random matrix prediction typical of a quantum chaotic system. However a transition to an insulating state, characterized by Poisson statistics, is observed by reducing the range of the two-body interaction. Close to the many-body metal-insulator transition, we show that spectral correlations share all features previously found in systems at the Anderson transition and in the proximity of the many-body localization transition. Our results suggest the potential relevance of SYK models in the context of many-body localization and also offer a starting point for the exploration of a gravity-dual of this phenomenon.

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Antonio M. García-García, Masaki Tezuka. 2018-01-10. Many-Body Localization in a finite-range Sachdev-Ye-Kitaev model. https://doi.org/10.1103/physrevb.99.054202

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