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arXiv · 1903.09491

Quantum criticality of granular SYK matter

Alexander Altland·Dmitry Bagrets·Alex Kamenev
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Abstract

We consider granular quantum matter defined by Sachdev-Ye-Kitaev (SYK) dots coupled via random one-body hopping. Within the framework of Schwarzian field theory, we identify a zero temperature quantum phase transition between an insulating phase at weak and a metallic phase at strong hopping. The critical hopping strength scales inversely with the number of degrees of freedom on the dots. The increase of temperature out of either phase induces a crossover into a regime of strange metallic behavior.

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Alexander Altland, Dmitry Bagrets, Alex Kamenev. 2019-03-22. Quantum criticality of granular SYK matter. https://doi.org/10.1103/physrevlett.123.106601

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