Momentum-dependent scaling exponents of nodal self-energies measured in strange metal cuprates and modelled using semi-holography

• Published in: Nature communications Vol. 15; no. 1; p. 4581
• Main Authors: Smit, S, Mauri, E, Bawden, L, Heringa, F, Gerritsen, F, van Heumen, E, Huang, Y K, Kondo, T, Takeuchi, T, Hussey, N E, Allan, M, Kim, T K, Cacho, C, Krikun, A, Schalm, K, Stoof, H T C, Golden, M S
• Format: Journal Article
• Language: English
• Published: England Nature Publishing Group 29.05.2024; Nature Portfolio
• Subjects: Cuprates; Doping; Electrons; Energy; Fermi liquids; Field theory; Holography; Metals; Momentum; Photoelectric emission; Physics; Superconductivity; Superconductors; Test stands; Theoretical physics; Thermodynamic properties
• ISSN: 2041-1723; 2041-1723
• DOI: 10.1038/s41467-024-48594-6

The anomalous strange metal phase found in high-T cuprates does not follow the conventional condensed-matter principles enshrined in the Fermi liquid and presents a great challenge for theory. Highly precise experimental determination of the electronic self-energy can provide a test bed for theoretical models of strange metals, and angle-resolved photoemission can provide this as a function of frequency, momentum, temperature and doping. Here we show that constant energy cuts through the nodal spectral function in (Pb,Bi) Sr La CuO have a non-Lorentzian lineshape, consistent with a self-energy that is k dependent. This provides a new test for aspiring theories. Here we show that the experimental data are captured remarkably well by a power law with a k-dependent scaling exponent smoothly evolving with doping, a description that emerges naturally from anti-de Sitter/conformal-field-theory based semi-holography. This puts a spotlight on holographic methods for the quantitative modelling of strongly interacting quantum materials like the cuprate strange metals.