Accurate theoretical fits to laser-excited photoemission spectra in the normal phase of high-temperature superconductors

Abstract

Anderson has recently proposed a theory of the strange metal state above T c in the high T c superconductors. 1 It is based on the idea that the unusual transport properties and spectral functions are caused by the strong Mott-Hubbard interactions and can be computed by using the formal apparatus of Gutzwiller projection. In ref. 1 Anderson computed only the tunneling spectrum and the power-law exponent of the infrared conductivity. He had calculated the energy distribution curves (EDCs) in angle resolved photoemission spectroscopy (ARPES) but was discouraged when these differed radically from the best ARPES measurements available at the time, and did not include them. In this letter we compare the spectral functions computed within Anderson's model to the novel laser-ARPES data of Dessau's group. 2,3 These are found to capture the shape of the experimental EDCs with unprecedented accuracy and in principle have only one free parameter.

Extremely Correlated Fermi-Liquid Description of Normal-State ARPES in Cuprates

“…14. We find an excellent fit quality, at least comparable to CADS [14]. The gray line in panel (a) shows our calculation for k > k F .…”

“…As shown in the panel d, the ECFL fit remains good by adjusting η, whether or not the extrinsic background is subtracted. In contrast, we find that the CADS theory, notwithstanding its notable successes [14,24], cannot cope with even the background subtracted data (Fig. 3e), giving too steep a fall off towards the left.…”

Transport anomalies of the strange metal: Resolution by hidden Fermi liquid theory

“…In Ref. 11 and related papers 14 we have shown that the form of the single-particle Green's function at absolute zero is the simple expression,…”

“…They can be expected to have rather large electron-electron scattering, ⌫ ee , proportional to ͑k − k F ͒ 2 . In the one case in which we have accurate information, optimally doped Bi 2 Sr 2 CaCu 2 O 8+␦ ͑BiSCCO͒, 14 the coefficient is…”

The origin and non-quasiparticle nature of Fermi arcs in Bi2Sr2CaCu2O8+δ

“…For example, gap values have been predominantly measured using the approximate 'midpoint of leading edge' 15 or 'peak separation of symmetrized spectra' 1,2 techniques, each of which is known to fail in many limits. Phenomenological models 16 have also been used to fit gapped energy distribution curves 17 (EDCs), but because the EDC lineshape is not yet understood 18 , these fittings are not obviously better than the approximate measures.…”