Direct Observation of Orbital Hybridisation in a Cuprate Superconductor
Abstract
The minimal ingredients to explain the essential physics of layered copper-oxide (cuprates= materials remains heavily debated. Effective low energy single-band models of the copper-oxygen orbitals are widely used because there exists no strong experimental evidence supporting multiband structures. Here we report angle-resolved photoelectron spectroscopy experiments on La-based cuprates that provide direct observation of a two-band structure. This electronic structure, qualitatively consistent with density functional theory, is parametrised by a two-orbital ( and ) tight-binding model. We quantify the orbital hybridisation which provides an explanation for the Fermi surface topology and the proximity of the van-Hove singularity to the Fermi level. Our analysis leads to a unification of electronic hopping parameters for single-layer cuprates and we conclude that hybridisation, restraining d-wave pairing, is an important optimisation element for superconductivity.
Keywords
Cite
@article{arxiv.1707.08491,
title = {Direct Observation of Orbital Hybridisation in a Cuprate Superconductor},
author = {Christian E. Matt and D. Sutter and A. M. Cook and Y. Sassa and M. Mansson and O. Tjernberg and L. Das and M. Horio and D. Destraz and C. G. Fatuzzo and K. Hauser and M. Shi and M. Kobayashi and V. Strocov and P. Dudin and M. Hoesch and S. Pyon and T. Takayama and H. Takagi and O. J. Lipscombe and S. M. Hayden and T. Kurosawa and N. Momono and M. Oda and T. Neupert and Johan Chang},
journal= {arXiv preprint arXiv:1707.08491},
year = {2018}
}
Comments
supplementary material available on request