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arXiv · 2003.09766

Subsystem R\'enyi Entropy of Thermal Ensembles for SYK-like models

Pengfei Zhang·Chunxiao Liu·Xiao Chen
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Abstract

The Sachdev-Ye-Kitaev model is an $N$-modes fermionic model with infinite range random interactions. In this work, we study the thermal R\'enyi entropy for a subsystem of the SYK model using the path-integral formalism in the large-$N$ limit. The results are consistent with exact diagonalization [1] and can be well approximated by thermal entropy with an effective temperature [2] when subsystem size $M\leq N/2$. We also consider generalizations of the SYK model with quadratic random hopping term or $U(1)$ charge conservation.

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Pengfei Zhang, Chunxiao Liu, Xiao Chen. 2020-03-21. Subsystem R\'enyi Entropy of Thermal Ensembles for SYK-like models. https://doi.org/10.21468/scipostphys.8.6.094

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