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arXiv · 1603.05246

Numerical study of fermion and boson models with infinite-range random interactions

Wenbo Fu·Subir Sachdev
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Abstract

We present numerical studies of fermion and boson models with random all-to-all interactions (the SYK models). The high temperature expansion and exact diagonalization of the $N$-site fermion model are used to compute the entropy density: our results are consistent with the numerical solution of $N=\infty$ saddle point equations, and the presence of a non-zero entropy density in the limit of vanishing temperature. The exact diagonalization results for the fermion Green's function also appear to converge well to the $N=\infty$ solution. For the hard-core boson model, the exact diagonalization study indicates spin glass order. Some results on the entanglement entropy and the out-of-time-order correlators are also presented.

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Wenbo Fu, Subir Sachdev. 2016-04-06. Numerical study of fermion and boson models with infinite-range random interactions. https://doi.org/10.1103/physrevb.94.035135

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