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arXiv · 1607.00694

Sachdev-Ye-Kitaev Model as Liouville Quantum Mechanics

Dmitry Bagrets·Alexander Altland·Alex Kamenev
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Abstract

We show that the proper inclusion of soft reparameterization modes in the Sachdev-Ye-Kitaev model of $N$ randomly interacting Majorana fermions reduces its long-time behavior to that of Liouville quantum mechanics. As a result, all zero temperature correlation functions decay with the universal exponent $\propto τ^{-3/2}$ for times larger than the inverse single particle level spacing $τ\gg N\ln N$. In the particular case of the single particle Green function this behavior is manifestation of the zero-bias anomaly, or scaling in energy as $ε^{1/2}$. We also present exact diagonalization study supporting our conclusions.

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Dmitry Bagrets, Alexander Altland, Alex Kamenev. 2016-07-03. Sachdev-Ye-Kitaev Model as Liouville Quantum Mechanics. https://doi.org/10.1016/j.nuclphysb.2016.08.002

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