Kernel polynomial representation of imaginary-time Green's functions

Abstract

Inspired by the recent proposed Legendre orthogonal polynomial representation of imaginary-time Green's functions, we develop an alternate representation for the Green's functions of quantum impurity models and combine it with the hybridization expansion continuous-time quantum Monte Carlo impurity solver. This representation is based on the kernel polynomial method, which introduces various integral kernels to filter fluctuations caused by the explicit truncations of polynomial expansion series and improve the computational precision significantly. As an illustration of the new representation, we reexamine the imaginary-time Green's functions of single-band Hubbard model in the framework of dynamical mean-field theory. The calculated results suggest that with carefully chosen integral kernels the Gibbs oscillations found in previous orthogonal polynomial representation have been suppressed vastly and remarkable corrections to the measured Green's functions have been obtained.

7 pages, 6 figures

References in corpus (8)

• Continuous-time Monte Carlo methods for quantum impurity models
• The Kernel Polynomial Method
• Quantum Monte Carlo Impurity Solver for Cluster DMFT and Electronic Structure Calculations in Adjustable Base
• Hybridization expansion impurity solver: General formulation and application to Kondo lattice and two-orbital models
• Dynamical vertex approximation - a step beyond dynamical mean field theory
• Continuous-time auxiliary field Monte Carlo for quantum impurity models
• $i$QIST: An open source continuous-time quantum Monte Carlo impurity solver toolkit
• Hallmark of strong electronic correlations in LaNiO${}_3$: photoemission kink and broadening of fully occupied bands

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