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 present an efficient diagrammatic method to describe nonlocal correlationeffects in lattice fermion Hubbard-like models, which is based on a change ofvariables in the Grassmann path integrals. The new fermions are dual to theoriginal ones and correspond to weakly interacting quasiparticles in the caseof strong local correlations in the Hubbard model. The method starts withdynamical mean-field theory as a zeroth-order approximation and includesnon-local effects in a perturbative way. In contrast to cluster approaches,this method utilizes an exact transition to a dual set of variables. Ittherefore becomes possible to treat the irreducible vertices of an effective{\it single-impurity} problem as small parameters. This provides a veryefficient interpolation between band-like weak-coupling and atomic limits. Themethod is illustrated on the two-dimensional Hubbard model. Theantiferromagnetic pseudogap, Fermi-arc formations, and non-Fermi-liquid effectsdue to the van Hove singularity are correctly reproduced by the lowest-orderdiagrams. Extremum properties of the dual fermion approach are discussed interms of the Feynman variational principle.

Dual fermion approach to the two-dimensional Hubbard model: Antiferromagnetic fluctuations and Fermi arcs