English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

We address the effect of band filling on the effective electron mass $m^*$and the superconducting critical temperature $T_c$ in a electron-phonon system.We compare the vertex corrected theory with the non-crossing approximation ofthe Holstein model within a local approximation. We identify two regions of theelectron density where $m^*$ and $T_c$ are enhanced or decreased by theinclusion of the vertex diagrams. We show that the crossover between theenhancement at low density and the decrease towards half filling is almostindependent of the microscopic electron-phonon parameters. These differentbehaviors are explained in terms of the net sign of the vertex diagrams whichis positive at low densities and negative close to half filling. Predictions ofthe present theory for doped MgB$_2$, which is argued to be in the low densityregime, are discussed.Comment: 13 revtex pages, figures eps include

Band-filling effects on electron-phonon properties of normal and superconducting states