T-linear resistivity and Planckian dissipation in cuprates

The perfectly linear temperature dependence of the resistivity observed as T→0 in a variety of metals close to a quantum critical point (QCP) is a major puzzle of condensed matter physics. I will present resistivity measurements supporting that T-linear resistivity as T→0 is a generic property of cuprates, associated with a universal scattering rate [1]. We measured the low-T resistivity of the bi-layer cuprate Bi2212 just above its pseudogap critical point p* and found that it exhibits a T-linear dependence with the same slope as in the single-layer cuprate Nd-LSCO close to its own p*, despite their very different Fermi surfaces and structural, superconducting and magnetic properties. We then showed that the T-linear coefficient (per CuO₂ plane), noted A, for various cuprates presenting this phenomenon, is given by a universal relation implying a specific scattering rate for charge carriers in all these samples: 1/τ = h/2πk_BT, where h is the Planck constant and k_B is the Boltzmann constant. This specific scattering rate corresponds to what is called the Planckian limit, and works not only for hole-doped cuprates but also for electron-doped cuprates, despite the different nature of their QCP and strength of their electron correlations.
[1] Legros et al., Nat. Phys. 15, 142 (2019)

In collaboration with: Siham Benabib, Wojciech Tabis, Baptiste Vignolle, Laboratoire National des Champs Magnetiques Intenses,; Francis Laliberte, Maxime Dion, Maude le Lizaire, Unversite de Sherbrooke