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 propose efficient measurement procedures for the self-energy and vertexfunction of the Anderson impurity model within the hybridization expansioncontinuous-time quantum Monte Carlo algorithm. The method is based on themeasurement of higher-order correlation functions related to the quantitiesbeing sought through the equation of motion, a technique previously introducedin the NRG context. For the case of interactions of density-density type, theadditional correlators can be obtained at essentially no additionalcomputational cost. In combination with a recently introduced method forfiltering the Monte Carlo noise using a representation in terms of orthogonalpolynomials, we obtain data with unprecedented accuracy. This leads to anenhanced stability in analytical continuations of the self-energy or intwo-particle based theories such as the dual fermion approach. As anillustration of the method we reexamine the previously reported spin-freezingand high-spin to low-spin transitions in a two-orbital model withdensity-density interactions. In both cases, the vertex function undergoessignificant changes, which suggests significant corrections to the dynamicalmean-field solutions in dual fermion calculations.

Improved Estimators for the Self-Energy and Vertex Function in Hybridization Expansion Continuous-Time Quantum Monte Carlo Simulations