Friedel oscillations as a probe of fermionic quasiparticles

  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 A. Demler},
  journal={Physical Review B},
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… 
Disorder and interactions in high-temperature superconductors
This thesis is devoted to an in-depth examination of the various effects of disorder in the cuprate high-temperature superconductors. Disorder is ubiquitous in these materials and is central to a
Towards a quantitative description of tunneling conductance of superconductors : application to LiFeAs
Since the discovery of iron-based superconductors, a number of theories have been put forward to explain the qualitative origin of pairing, but there have been few attempts to make quantitative,
Minimal model of charge and pairing density waves in x-ray scattering experiments
Competing density waves play an important role in the mystery of high-temperature superconductors. In spite of the large amount of experimental evidence, the fundamental question of whether these
Multifaceted impact of a surface step on superconductivity in atomically thin films
Recent experiments show that an atomic step on the surface of atomically thin metallic films can strongly affect electronic transport. Here we reveal multiple and versatile effects that such a
Impurity with a resonance in the vicinity of the Fermi energy
We study an impurity with a resonance level whose position coincides with the Fermi energy of the surrounding Fermi gas. An impurity causes a rapid variation of the scattering phase shift for
Real-space dynamical mean-field theory of Friedel oscillations in strongly correlated electron systems
We study Friedel oscillations and screening effects of the impurity potential in the Hubbard model. Electronic correlations are accounted for by solving the real-space dynamical mean-field theory
Ground-state energy, density profiles, and momentum distribution of attractively interacting 1D Fermi gases with hard-wall boundaries: a Monte Carlo study
Motivated by the realization of hard-wall boundary conditions in experiments with ultracold atoms, we investigate the ground-state properties of spin-1/2 fermions with attractive interactions in a
Evolution of charge order topology across a magnetic phase transition in cuprate superconductors
Charge order is now accepted as an integral constituent of cuprate high-temperature superconductors, one that is intimately related to other electronic instabilities including antiferromagnetism and
Distinction between pristine and disorder-perturbed charge density waves in ZrTe3
A resonant X-ray diffraction study of ZrTe, a model CDW system, with focus on the influence of disorder, reports coexisting diffraction signals and anomalous slow dynamics of charge domains near the CDW transitionTemperature, suggesting as fingerprints of pristine and disorder-perturbed CDWs.


Quasiparticle interference and the interplay between superconductivity and density wave order in the cuprates
Scanning tunneling spectroscopy (STS) is a useful probe for studying the cuprates in the superconducting and pseudogap states. Here we present a theoretical study of the Z-map, defined as the ratio
Exploring quasiparticles in high-Tc cuprates through photoemission, tunneling, and x-ray scattering experiments
One of the key challenges in the field of high-temperature superconductivity is understanding the nature of fermionic quasiparticles. Experiments consistently demonstrate the existence of a second
Coherence Factors in a High-Tc Cuprate Probed by Quasi-Particle Scattering Off Vortices
F Fourier-transform scanning tunneling spectroscopy is used to reveal a magnetic-field dependence in quasi-particle scattering interference patterns that is sensitive to the sign of the anisotropic gap, and provides insights into the nature of electron pairing as well as quasi- particle scattering processes in unconventional superconductors.
Pairing Fluctuation Theory of Superconducting Properties in Underdoped to Overdoped Cuprates
Pseudogap phenomena in the cuprates are of interest not only because of the associated unusual normal-state properties, but more importantly because of the constraints which these phenomena impose on
Universal quantum oscillations in the underdoped cuprate superconductors
Every metal has an underlying Fermi surface that gives rise to quantum oscillations. So far, quantum oscillation measurements in the superconductor YBCO have been inconclusive owing to the structural
Quasiparticle scattering interference in high-temperature superconductors
We propose that the energy-dependent spatial modulation of the local density of states seen by Hoffman et al. [Science 297, 1148 (2002)] is due to the scattering interference of quasiparticles. In
Coherence and single-particle excitations in the high-temperature superconductors
This work compares gap energies, measured by different experimental techniques, for the copper oxide superconductors and shows that these reveal the existence of two distinct energy scales: Δp and Δc, which, in the overdoped regime, converge to approximately the same value, as would be the case for a BCS superconductor where pairs form and condense simultaneously.
Defects in correlated metals and superconductors
In materials with strong local Coulomb interactions, simple defects such as atomic substitutions strongly affect both macroscopic and local properties of the system. A nonmagnetic impurity, for
Giant Friedel Oscillations on the Beryllium(0001) Surface
Large-amplitude electron density oscillations were observed on a Be(0001) surface by means of variable-temperature scanning tunneling microscopy, and the amplitude of the waves for energies near the Fermi energy was anomalously large and inconsistent with the Friedel concept of screening.
Fourier transform spectroscopy of d-wave quasiparticles in the presence of atomic scale pairing disorder
The local density of states power spectrum of optimally doped Bi2Sr2CaCu2O8+x BSCCO has been interpreted in terms of quasiparticle interference peaks corresponding to an “octet” of scattering wave