Non-Fermi liquid behavior of scattering rate in three-orbital Emery model

Motivated by the recent findings on the T-linear electronic scattering rate in the two-dimensional Hubbard model, we have investigated the three-orbital Emery model and its temperature-dependent electronic and quasiparticle scattering rates by adopting dynamical cluster quantum Monte Carlo simulations. By focusing on two characteristic site energies εₚ of O-2p orbital relevant to cuprates and nickelates separately, our exploration discovered that, for εₚ=3.24 relevant to cuprates, the scattering rate can exhibit a linear-T dependence at low temperature for a range of intermediate densities. In contrast, for larger εₚ=6.0 presumably relevant to nickelates, a wide range of densities support a downturn of the scattering rate below the temperature scale T~0.1 with possibly two consecutive nearly linear-T regimes connected via a smooth crossover around T~0.1. Furthermore, the temperature dependent quasiparticle scattering rate generically departs from the unity slope as predicted by the Planckian dissipation theory. Our presented work provides valuable insights on the extensively studied three-orbital Emery model, particularly on the quantitative examination of non-Fermi liquid features of scattering rates.