2022/03/30 by Yung-Yeh Chang, Chang, Yung-Yeh, Hechang Lei +5
Physics and Astronomy · Materials Science · #Rare-earth and actinide compounds #Physics of Superconductivity and Magnetism #Iron-based superconductors research
paper · pdf · doi:10.48550/arxiv.2203.16362
Perfect T-linear resistivity associated with universal scattering rate: 1/τ=αkB T/ℏ with α∼ 1, so-called Planckian metal state, has been observed in the normal state of a variety of strongly correlated superconductors close to a quantum critical point. However, the microscopic origin of this intriguing phenomena and its link to quantum criticality still remains an outstanding open problem. In this work, we observe the quantum-critical T/B-scaling of the Planckian metal state in the resistivity and heat capacity of heavy-electron superconductor Ce1-xNdxCoIn5 in magnetic fields near the edge of antiferromagnetism, driven by critical Kondo hybridization at the critical doping xc ∼ 0.03. We further provide the first microscopic mechanism to account for the Planckian state in a quantum critical system based on the critical charge fluctuations near Kondo breakdown transition at xc within the quasi-two-dimensional Kondo-Heisenberg lattice model. This mechanism simultaneously captures the observed universal Planckian scattering rate as well as the quantum-critical scaling and power-law divergence in thermodynamic observables near criticality. Our mechanism is generic to Planckian metal states in a variety of quantum critical superconductors near Kondo destruction.