Physical review. B./Physical review. B
Non-Fermi-liquid behavior of the scattering rate in the three-orbital Emery model
Tianzong Mao, Mi Jiang
Abstract
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 ${\ensuremath{\epsilon}}_{p}$ of $\mathrm{O-2}p$ orbital relevant to cuprates and nickelates separately, our exploration discovered that, for ${\ensuremath{\epsilon}}_{p}=3.24$ 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 ${\ensuremath{\epsilon}}_{p}=6.0$ presumably relevant to nickelates, a wide range of densities support a downturn of the scattering rate below the temperature scale $T\ensuremath{\sim}0.1$ with possibly two consecutive nearly linear-$T$ regimes connected via a smooth crossover around $T\ensuremath{\sim}0.1$. 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.