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Researchers from the CNRS and the Université de Sherbrooke have discovered a universal law for the electronic properties of high temperature superconductors. They exposed the superconductors to an intense magnetic field in order to weaken them and reveal their underlying properties. They measured electrical resistivity variations down to -263 ° C and developed a predictive model that can be applied to several families of high temperature superconductors.
This energy dissipation speed limit is related to the numerical value of the Planck constant, the fundamental quantity of quantum mechanics representing the smallest possible action in nature.
Natalie Wolchover of Atlantic described how superconductor research could be a conceptual breakthrough in understanding the physics of superconductors. There appears to be a holographic duality that mathematically links the scrambled quantum particle systems, such as those of strange metals, to imaginary black holes of a larger size.
Black holes, quantum systems, superconductors and Planck's constant appear to be related.
Nature Physics – Universal T resistivity and Planckian dissipation in overdoped cuprates
Electrons in a variety of ceramic crystals from cuprate superconductors appear to dissipate energy as quickly as possible, apparently striking a fundamental quantum velocity limit. Older studies have shown that other exotic superconducting compounds – strontium ruthenates, pnictures, tetramethyltetrathiafulvalenes – also burn energy at a rate that appears to be maximal.
Summary – Universal T resistivity and Planckian dissipation in overdoped cuprates
The perfectly linear temperature dependence of the electrical resistivity observed in the T → 0 form in a variety of metals close to a quantum critical point is a major puzzle in the physics of condensed matter. We show here that the T-linear resistivity as T → 0 is a generic property of cuprates, associated with a universal diffusion rate. We measured the low-temperature resistivity of Bi2Sr2CaCu2O8 + δ bilayer cuprate and found that it exhibited a T-linear dependence with the same slope as in the Bi2Sr2CuO6 + δ, La1.6-xNd0.4SrxCuOxSrxx2 monolayer cuprates despite their Fermi surfaces and their very different structural, superconducting and magnetic properties. We then show that the T-linear coefficient (by CuO2 plane), A1 □, is given by the universal relation A1 □ TF = h / 2e2, where e is the electronic charge, h is the Planck constant and TF is the temperature of Fermi. This relation, obtained by assuming that the diffusion rate 1 / τ of the charge carriers reaches the Planckian limit according to which ħ / τ = kBT, functions not only for the cuprates doped with the hole, but also for the cuprates doped with the electrons in spite of the different nature of their point quantum critical values and the strength of their electronic correlations.
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