Join the Quantum Matter group in a seminar titled "Low energy phenomenology of overdoped cuprates based on realistic impurity potentials" with Prof. David Broun (Simon Fraser University).
Date: 27 January 2023, 2:00PM - 3:00PM
Zoom Link: https://bristol-ac-uk.zoom.us/j/95952361031?pwd=Qm12cUdFcWhIQUUvdGZZTVVtMlNaQT09
Meeting ID: 959 5236 1031
Passcode: 185925
Abstract:
Recent experiments on hole-doped overdoped cuprates, including measurements of superfluid density [1] and THz conductivity [2] in La2-xSrxCuO4, have been interpreted as implying the breakdown of the Landau–BCS paradigm in the overdoped regime. In contrast, a phenomenological model based on realistic, ARPES-derived bandstructures and Fermi-liquid renormalizations has been shown to capture essentially all aspects of the thermodynamic and transport properties [3], including superfluid density [4] and THz conductivity [5], provided the unusual effects of weak, out-of-plane dopant impurities are properly accounted for. For simplicity, this phenomenology was initially based on a mixture of Born and unitarity-limit point scatterers, a possible shortcoming of the theory. In our most recent work [6], the point scatterers have been replaced by realistic impurity potentials computed using ab-initio DFT calculations of the defect potentials. These finite-range potentials generate strongly q-dependent scattering amplitudes, leading to significant forward scattering and vertex corrections, which have been included in the model. The van Hove singularity in La2-xSrxCuO4 also requires special treatment. What emerges is a robust and realistic model of the overdoped cuprates, showing that a d-wave BCS superconductor, emerging from a Fermi liquid normal state, provides a good account of the overdoped cuprates.