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arXiv · 1701.07081

Instability of the non-Fermi liquid state of the Sachdev-Ye-Kitaev Model

Zhen Bi·Chao-Ming Jian·Yi-Zhuang You·Kelly Ann Pawlak·Cenke Xu
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Abstract

We study a series of perturbations on the Sachdev-Ye-Kitaev (SYK) model. We show that the chaotic non-Fermi liquid phase described by the ordinary $q = 4$ SYK model has marginally relevant/irrelevant (depending on the sign of the coupling constants) four-fermion perturbations allowed by symmetry. Changing the sign of one of these four-fermion perturbations leads to a continuous chaotic-nonchaotic quantum phase transition of the system accompanied by a spontaneous time-reversal symmetry breaking. Starting with the SYK$_q$ model with a $q-$fermion interaction, similar perturbations can lead to a series of new interacting conformal field theory fixed points.

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Zhen Bi, Chao-Ming Jian, Yi-Zhuang You, Kelly Ann Pawlak, Cenke Xu. 2017-01-24. Instability of the non-Fermi liquid state of the Sachdev-Ye-Kitaev Model. https://doi.org/10.1103/physrevb.95.205105

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