Quantum Matter Seminar 27th January: "Low energy phenomenology of overdoped cuprates based on realistic impurity potentials"

23 January 2023

This seminar is on the role of impurities in the phenomenology of overdoped cuprates. It will be presented by Professor David Broun (Simon Fraser University).

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 In our most recent work [6], the point scatterers have been replaced by realistic impurity potentials computed using ab-initio DFT calculations of the defect potentials.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.

Further information

[1]. I. Bozovic et al., Nature 536, 309 (2016).

[2]. F. Mahmood et al., Phys. Rev. Lett. 122, 027003 (2019).

[3]. N. R. Lee-Hone et al., Phys. Rev. R 2, 013228 (2020).

[4]. N. R. Lee-Hone et al., Phys. Rev. B 96, 024501 (2017).

[5]. N. R. Lee-Hone et al., Phys. Rev. B 98 054506 (2018).

[6]. H. U. Özdemir et al., Phys. Rev. B 106, 184510 (2022).