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arXiv · 2103.12110

Non-Fermi liquid behavior in the Sachdev-Ye-Kitaev model for a one dimensional incoherent semimetal

Geo Jose·Kangjun Seo·Bruno Uchoa
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Abstract

Abstract We study a two-band dispersive Sachdev-Ye-Kitaev (SYK) model in 1 + 1 dimension. We suggest a model that describes a semimetal with quadratic dispersion at half-filling. We compute the Green's function at the saddle point using a combination of analytical and numerical methods. Employing a scaling symmetry of the Schwinger-Dyson equations that becomes transparent in the strongly dispersive limit, we show that the exact solution of the problem yields a distinct type of non-Fermi liquid with sublinear $\rho\propto T^{2/5}$ temperature dependence of the resistivity. A scaling analysis indicates that this state corresponds to the fixed point of the dispersive SYK model for a quadratic band touching semimetal.

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Geo Jose, Kangjun Seo, Bruno Uchoa. 2021-03-22. Non-Fermi liquid behavior in the Sachdev-Ye-Kitaev model for a one dimensional incoherent semimetal. https://doi.org/10.1103/physrevresearch.4.013145

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