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arXiv · 2601.04330

Four-point function of the complex Sachdev-Ye-Kitaev model at finite chemical potential

Can Onur Akyuz·Erick Arguello Cruz·Ludo Fraser-Taliente·Grigory Tarnopolsky
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Abstract

It is known that, for a range of chemical potentials, the infrared behavior of the complex Sachdev-Ye-Kitaev (cSYK) model is governed by a 1D Nearly Conformal Field Theory (NCFT$_{1}$), thereby realizing a continuous line of NCFTs. A finite chemical potential $\mu$ introduces an asymmetry parameter $\mathscr{E}$ into the cSYK fermion two-point function in the conformal limit. In this work, we compute the cSYK four-point function in the conformal limit for an arbitrary value of $\mathscr{E}$ at leading order in $1/N$. We show that the result is fully consistent with the NCFT$_{1}$ structure of the cSYK model and use it to extract the structure constants for correlation functions of two complex fermions with bilinear operators.

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Can Onur Akyuz, Erick Arguello Cruz, Ludo Fraser-Taliente, Grigory Tarnopolsky. 2026-01-07. Four-point function of the complex Sachdev-Ye-Kitaev model at finite chemical potential. https://arxiv.org/abs/2601.04330

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