Non-equilibrium Sachdev-Ye-Kitaev model with quadratic perturbation

We consider a non-equilibrium generalization of the mixed SYK$_4$+SYK$_2$ model and calculate the energy dissipation rate $W(ω)$ that results due to periodic modulation of random quadratic matrix elements with a frequency $ω$. We find that $W(ω)$ possesses a peak at $ω$ close to the polaron energy splitting $ω_R$ found recently (PRL 125, 196602), demonstrating the physical significance of this energy scale. Next, we study the effect of energy pumping with a finite amplitude at the resonance frequency $ω_R$ and calculate, in presence of this pumping, non-equilibrium dissipation rate due to low-frequency parametric modulation. We found an unusual phenomenon similar to "dry friction" in presence of pumping.