d-wave superconductivity from electron-phonon interactions

Abstract

I examine electron-phonon mediated superconductivity in the intermediate coupling and phonon frequency regime of the quasi-2D Holstein model. I use an extended Migdal-Eliashberg theory which includes vertex corrections and spatial fluctuations. I find a d-wave superconducting state that is unique close to half-filling. The order parameter undergoes a transition to s-wave superconductivity on increasing filling. I explain how the inclusion of both vertex corrections and spatial fluctuations is essential for the prediction of a d-wave order parameter. I then discuss the effects of a large Coulomb pseudopotential on the superconductivity (such as is found in contemporary superconducting materials like the cuprates), which results in the destruction of the s-wave states, while leaving the d-wave states unmodified.

4 pages, 4 figures

References in corpus (7)

• Evidence for ubiquitous strong electron-phonon coupling in high-temperature superconductors
• Quantum Cluster Theories
• Nonlocal Dynamical Correlations of Strongly Interacting Electron Systems
• The Dynamical Cluster Approximation: Non-Local Dynamics of Correlated Electron Systems
• A Quantum Monte Carlo algorithm for non-local corrections to the Dynamical Mean-Field Approximation
• Electron and phonon dispersions of the two dimensional Holstein model: Effects of vertex and non-local corrections
• Superconducting states of the quasi-2D Holstein model: Effects of vertex and non-local corrections

Cited by in corpus (17)

• Superconductivity in a Hubbard-Froehlich Model and in cuprates
• Unconventional superconducting pairing by conventional phonons
• Superlight small bipolarons
• Breakdown of Migdal--Eliashberg theory via catastrophic vertex divergence at low phonon frequency
• Crossover between electron-electron and electron-phonon mediated pairing on the Kagome lattice
• Electronic structure, electron-phonon coupling and superconductivity in noncentrosymmetric ThCoC2 from ab initio calculations
• Charge density wave in single-layer Pb/Ge(111) driven by Pb-substrate exchange interaction
• Possible propagation of the Zhang-Rice singlet as a probable Cooper channel in the $Cu{O}_2$ planes
• Ubiquitous light real-space pairing from long-range hopping and interactions
• Stochastic path-integral approach for predicting the superconducting temperatures of anharmonic solids
• Charge correlations suppress unconventional pairing in the Holstein model
• Unconventional pairing in bipolaronic theories
• Bipolaron formed through electron-hole excitation
• Doping dependence and multichannel mediators of superconductivity: Calculations for a cuprate model
• Real-space d-wave superconductivity from weak attraction
• Downfolding the Su-Schrieffer-Heeger model
• Unconventional superconductivity mediated solely by isotropic electron-phonon interaction