English

Friedel Oscillations as a Probe of Fermionic Quasiparticles

Strongly Correlated Electrons 2016-05-12 v2 Superconductivity

Abstract

When immersed in a see of cold electrons, local impurities give rise to density modulations known as Friedel oscillations. In spite of the generality of this phenomenon, the exact shape of these modulations is usually computed only for non-interacting electrons with a quadratic dispersion relation. In actual materials, one needs to take into account several additional factors, such as (i) the details of the band structure, (ii) the lifetime of quasiparticles, (iii) in superconductors, the presence of a pairing gap. Studying how these effects influence Friedel oscillations is a viable way to access the properties of fermionic excitations in strongly-correlated materials. In this work we analyze the signatures of Friedel oscillations in STM and X-ray scattering experiments, focusing on the concrete example of cuprates superconductors. A detailed comparison with recent experiments reveals a rich interplay between local modulation of the chemical potential and of the pairing gap.

Keywords

Cite

@article{arxiv.1507.04345,
  title  = {Friedel Oscillations as a Probe of Fermionic Quasiparticles},
  author = {Emanuele G. Dalla Torre and David Benjamin and Yang He and David Dentelski and Eugene Demler},
  journal= {arXiv preprint arXiv:1507.04345},
  year   = {2016}
}

Comments

18 pages, 14 figures, content updated, now including a discussion on c-axis correlations