Universal quench dynamics of lattice $q$ fermion Yukawa Sachdev-Ye-Kitaev model

Abstract

We study the quantum quench of the Yukawa Sachdev-Ye-Kitaev model and one of its lattice extensions with $q$ fermions and one boson. Several equilibrium properties are computed for general $q$ with different parameter scaling within the large-$N$ dynamical mean field scheme. The non-Fermi liquid quench dynamics are studied by integrating the Kadanoff-Baym equations for switching off the lattice term with constant Yukawa coupling or quenching to different final Yukawa couplings. The post-quench oscillations and relaxation dynamics are insensitive to the quench amplitudes deep inside the non-Fermi liquid phase. With weak lattice coupling quenches, we find universal thermalization dynamics similar to the SYK model; however, with two temperatures and two distinct relaxation rates for bosons and fermions, both signal Planckian relaxations without quasiparticles, as in strange metals.