Non-Fermi liquid phase and linear-in-temperature scattering rate in overdoped two-dimensional Hubbard model

Significance Most metals display an electron-scattering rate 1 / τ that follows 1 / τ ∼ T 2 at low temperatures, as prescribed by Fermi liquid theory. But there are important exceptions. One of the most prominent examples is the “strange” metal regime in overdoped cuprate supercondcutors, which exhibits a linear T dependence of the scattering rate 1 / τ ∼ T that reaches a putative Planckian limit. Here, using cutting-edge computational approaches, we show that T -linear scattering rate can emerge from the overdoped Hubbard model at low temperatures. Our results agree with cuprate experiments in various aspects but challenge the Planckian limit. Finally, by identifying antiferromagnetic fluctuations as the physical origin of the T -linear scattering rate, we discover the microscopic mechanism of strange metallicity in cuprates.