Emergent electronic phases in cuprate strange metals

In this thesis, the electronic structure of (Pb,Bi)_²Sr_²−xLaxCuO6+δ (or Bi2201), is investigated using high resolution Angle Resolved Photoemission Spectroscopy (ARPES). The phase diagram, showing the electronic phases of Bi2201 as function of doping and temperature is brought in line with those of other major cuprates, by determining the dependence of superconductivity and the pseudogap state on holedoping in a combined magnetotransport and ARPES study. Next, the spectral function in the nodal direction of the Brillouin zone is studied as function of temperature and doping. The electronic interactions are found to be excellently described by a model containing powerlaws with a momentum dependent scaling exponent. Such a mathematical description follows naturally from the holographic duality, where strongly interacting systems such as the cuprates can be modelled by a dual, gravitational problem in the framework of general relativity. This work constitutes the first time that real ARPES data is compared to holographic calculations. In the last part of the thesis, the Fermi surface of Bi2201 is investigated more closely. Density functional theory calculations using the crystal parameters as determined by X-ray diffraction are found to accurately describe the Fermi surface, and underpin a scenario where self-energy in the two nodal directions is anisotropic. In the overdoped region the states around the antinode are found to get increasingly coherent, something expressed in the width of the spectral function for k = kF . These findings can possibly account for anomalous missing carriers, as has been observed in transport experiments.