scholarly journals Fermi Blockade of the Electron-phonon Interaction: Why Strong Coupling Effects May Not Be Seen in Optimally Doped High Temperature Superconductors

2020 ◽  
Author(s):  
Andrey Mishchenko ◽  
Naoto Nagaosa ◽  
Nikolay Prokof'ev
Keyword(s):  
High Temperature ◽  
High Temperature Superconductors ◽  
Two Dimensional ◽  
Phonon Interaction ◽  
Strong Electron ◽  
Electron Phonon Interaction ◽  
Holstein Model ◽  
Bold Line ◽  
Spin Polarized ◽  
Migdal's Theorem

Abstract We study how manifestations of strong electron-phonon interaction (EPI) depend on the carrier concentration by solving the two-dimensional Holstein model for the spin-polarized fermions using an approximation free bold-line diagrammatic Monte Carlo (BDMC) method. We show that the strong EPI, obviously present at very small Fermion concentration, is masked by the Fermi blockade effects and Migdal's theorem to the extent that it manifests itself as moderate one at large carriers densities. Suppression of strong EPI fingerprints is in agreement with experimental observations in doped high temperature superconductors.

scholarly journals Fermi blockade of the strong electron-phonon interaction in optimally doped high temperature superconductors

2021 ◽  
Author(s):  
Andrey Mishchenko ◽  
Naoto Nagaosa ◽  
Nikolay Prokof'ev ◽  
Igor Tupitsyn
Keyword(s):  
High Temperature ◽  
High Temperature Superconductors ◽  
Two Dimensional ◽  
Phonon Interaction ◽  
Strong Electron ◽  
Electron Phonon Interaction ◽  
Holstein Model ◽  
Bold Line ◽  
Spin Polarized ◽  
Migdal's Theorem

Abstract We study how manifestations of strong electron-phonon interaction (EPI) depend on the carrier concentration by solving the two-dimensional Holstein model for the spin-polarized fermions using an approximation free bold-line diagrammatic Monte Carlo (BDMC) method. We show that the strong EPI, obviously present at very small Fermion concentration, is masked by the Fermi blockade effects and Migdal's theorem to the extent that it manifests itself as moderate one at large carriers densities. Suppression of strong EPI fingerprints is in agreement with experimental observations in doped high temperature superconductors.

scholarly journals The Gap and the Upper Critical FieldHc2as Function of Doping for High-TcCuprates

2014 ◽  
Vol 2014 ◽  
pp. 1-7 ◽  
Author(s):  
S. Orozco ◽  
R. M. Méndez-Moreno ◽  
M. A. Ortiz
Keyword(s):  
High Temperature ◽  
Critical Field ◽  
Energy Gap ◽  
High Temperature Superconductors ◽  
Upper Critical Field ◽  
Superconducting Gap ◽  
Phonon Interaction ◽  
As Doping ◽  
Electron Phonon Interaction ◽  
Wave Symmetry

The relation between thed-wave superconducting gapΔ0and the specific heat obtained with the Volovik effect is used to determine the upper critical fieldHc2as doping function, for high-temperature superconductors. A two-components model withd-wave symmetry, within the BCS framework, is introduced to describe the superconducting state. Generalized Fermi surface topologies are used in order to increase the density of states at the Fermi level, allowing the high-Tcvalues observed. The electron-phonon interaction is considered the most relevant mechanism for the high-Tccuprates, where the available phonon energy is provided by the half-breathing modes. The energy gap valuesΔ0calculated with this model are introduced to describe the variation of the upper critical fieldHc2as function of doping, forLa2-xSrxCuO4.

THE EFFECT OF STRONG ELECTRON-PHONON INTERACTIONS ON THE INFRARED REFLECTANCE IN HIGH-Tc SUPERCONDUCTORS

1991 ◽  
Vol 05 (20) ◽  
pp. 1361-1365 ◽  
Author(s):  
S. Y. TIAN ◽  
M. H. LI ◽  
Z. X. ZHAO
Keyword(s):  
High Temperature Superconductors ◽  
Peak Position ◽  
Superconducting Gap ◽  
High Tc Superconductors ◽  
Phonon Interaction ◽  
Phonon Softening ◽  
Strong Electron ◽  
High Tc ◽  
Electron Phonon Interaction ◽  
And Shifts

We show that the model of charge-transfer fluctuation with LO phonons can unify the interpretation of the infrared features and the phonon softening at about 55 meV measured by neutron scattering experiments in high temperature superconductors. Based upon this model we demonstrate that reflectivity ratio of superconducting state to normal state is strongly modified as a result of strong electron-phonon interaction which is different from Holstein mechanism. A broad peak in the ratio reflectivity develops around the peak position of different neutron phonon density of states. This peak becomes stronger and shifts to a higher frequency as the coupling increases at lower temperatures. This situation complicates the interpretation of the ratio reflectivity peak as the superconducting gap.

Electron-phonon interaction in high-temperature superconductors

1993 ◽  
Vol 163 (2) ◽  
pp. 61 ◽  
Author(s):  
V.M. Svistunov ◽  
M.B. Belogolovskii ◽  
A.I. Khachaturov
Keyword(s):  
High Temperature ◽  
High Temperature Superconductors ◽  
Phonon Interaction ◽  
Electron Phonon Interaction
Sign in / Sign up

Export Citation Format

Share Document