Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

Recent Progress in Many-Body Theories

Fluctuation Effects in Electron Systems: Their Role in Electron-Pairing Mechanisms

Neil William Ashcroft

Published Jan 1, 1988• 0 citations
Publisher
DOI
10.1007/978-1-4613-0973-4_4

Related papers

Role of vertex corrections in the spin-fluctuation–mediated pairing mechanism

Z. B Huang, Werner R. Hanke, Enrico Arrigoni

We study numerically and partly diagrammatically the renormalization of the electron-spin interaction or vertex in a two-dimensional one-band Hubbard model with spin-fluctuation momentum transfer q = (π,π). We find that the renormalized electron-spin vertex decreases quite generally with decreasing temperature at all doping densities. As a combination of two concurring effects, i.e. the decrease of the vertex and the increase of the spin susceptibility, the effective pairing interaction increases with lowering temperature in the intermediate-correlation regime, but flattens off in the strong-correlation regime. Our findings indicate that in the high- T c cuprates the pairing mediated by antiferromagnetic spin fluctuations is substantially reduced due to vertex corrections.

arXiv:cond-mat/0408564•Europhysics Letters (EPL)•Aug 16, 2005•6 citations

Effects of disorder on the electron pairing

Raúl Oviedo‐Roa, C. Wang, Oracio Navarro

Journal of Low Temperature Physics•Nov 1, 1996•4 citations

Exchange and Correlation in Many-Electron Systems

Yue Wang

•Jan 1, 1991•0 citations

d-wave superconductivity in a strongly correlated electron-phonon system

Marcin Mierzejewski, J. Zieliński, P. Entel

The problem of phonon-mediated and phonon-free contributions to d-wave superconductivity in the two-dimensional Hubbard model has been addressed. Strong local correlations (U\ensuremath{\rightarrow}\ensuremath{\infty} limit) have been incorporated in the slave boson formulation. In order to consider electron-boson and electron-phonon coupling on equal footing, fluctuations of the auxiliary boson fields over their mean-field value have been introduced. The magnitude of effective pairing interactions derived with the help of a canonical transformation indicates that within the weak-coupling theory, phonon-mediated pairing plays a marginal role and can be dominated by a phonon-free pairing mechanism. On the other hand, in the strong-coupling limit (Eliashberg formulation), electron-phonon and electron-phonon-boson interactions can significantly enhance the superconducting transition temperature. It is also shown that Coulomb correlations together with the electron-phonon interaction can effectively stabilize a d-wave superconducting state. \textcopyright{} 1996 The American Physical Society.

Physical review. B, Condensed matter•Jan 1, 1996•19 citations

Electron–Electron Interaction and Correlations

Jenő Sólyom

Springer eBooks•Jan 1, 2010•1 citation

A New Perspective to Study the Correlation Effect of the Three-Dimensional Electron Gas

Zhi‐Ming Yu, Yu-Liang Liu

The phase field, which originates from the electronic interaction, plays an important role in describing a strongly correlated system in one dimension. However, in higher dimensions the effect of phase field cannot be obviously understood. With the eigenfunctional theory, we calculate the pair distribution function of the three-dimensional electron gas to study the relationship between the phase field and the electronic correlation effect and show that at zero temperature the correlation effect of the electrons is mainly dominated by the phase fluctuation, which is produced by the electronic interaction. We also discuss the failure of random phase approximation in studying the correlation function when the correlation effect is strong in the view of the phase field.

Chinese Physics Letters•Jan 1, 2014•1 citation
We study numerically and partly diagrammatically the renormalization of the electron-spin interaction or vertex in a two-dimensional one-band Hubbard model with spin-fluctuation momentum transfer q = (π,π). We find that the renormalized electron-spin vertex decreases quite generally with decreasing temperature at all doping densities. As a combination of two concurring effects, i.e. the decrease of the vertex and the increase of the spin susceptibility, the effective pairing interaction increases with lowering temperature in the intermediate-correlation regime, but flattens off in the strong-correlation regime. Our findings indicate that in the high- T c cuprates the pairing mediated by antiferromagnetic spin fluctuations is substantially reduced due to vertex corrections.
The problem of phonon-mediated and phonon-free contributions to d-wave superconductivity in the two-dimensional Hubbard model has been addressed. Strong local correlations (U\ensuremath{\rightarrow}\ensuremath{\infty} limit) have been incorporated in the slave boson formulation. In order to consider electron-boson and electron-phonon coupling on equal footing, fluctuations of the auxiliary boson fields over their mean-field value have been introduced. The magnitude of effective pairing interactions derived with the help of a canonical transformation indicates that within the weak-coupling theory, phonon-mediated pairing plays a marginal role and can be dominated by a phonon-free pairing mechanism. On the other hand, in the strong-coupling limit (Eliashberg formulation), electron-phonon and electron-phonon-boson interactions can significantly enhance the superconducting transition temperature. It is also shown that Coulomb correlations together with the electron-phonon interaction can effectively stabilize a d-wave superconducting state. \textcopyright{} 1996 The American Physical Society.
The phase field, which originates from the electronic interaction, plays an important role in describing a strongly correlated system in one dimension. However, in higher dimensions the effect of phase field cannot be obviously understood. With the eigenfunctional theory, we calculate the pair distribution function of the three-dimensional electron gas to study the relationship between the phase field and the electronic correlation effect and show that at zero temperature the correlation effect of the electrons is mainly dominated by the phase fluctuation, which is produced by the electronic interaction. We also discuss the failure of random phase approximation in studying the correlation function when the correlation effect is strong in the view of the phase field.