6533b829fe1ef96bd1289b43
RESEARCH PRODUCT
Vertex corrections for positive-definite spectral functions of simple metals
R. Van LeeuwenA.-m. UimonenGianluca StefanucciYaroslav Pavlyukhsubject
vertex correctionshomogeneous electron gasMonte Carlo methodFOS: Physical sciencesGeneral Physics and AstronomyPositive-definite matrixspectral function7. Clean energy01 natural sciences010305 fluids & plasmasSettore FIS/03 - Fisica della Materiasymbols.namesakePhysics and Astronomy (all)Condensed Matter - Strongly Correlated Electrons0103 physical sciencesVertex model010306 general physicsPlasmonPhysicsStrongly Correlated Electrons (cond-mat.str-el)ta114ScatteringFermi levelVertex functionQuantum electrodynamicssymbolsFermi gasdescription
We present a systematic study of vertex corrections in the homogeneous electron gas at metallic densities. The vertex diagrams are built using a recently proposed positive-definite diagrammatic expansion for the spectral function. The vertex function not only provides corrections to the well known plasmon and particle-hole scatterings, but also gives rise to new physical processes such as generation of two plasmon excitations or the decay of the one-particle state into a two-particles-one-hole state. By an efficient Monte Carlo momentum integration we are able to show that the additional scattering channels are responsible for the bandwidth reduction observed in photoemission experiments on bulk sodium, appearance of the secondary plasmon satellite below the Fermi level, and a substantial redistribution of spectral weights. The feasibility of the approach for first-principles band-structure calculations is also discussed.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2016-07-14 |