Computing Exact Self-Energies with Polynomial Expansion
Strongly Correlated Electrons
2015-11-04 v1
Abstract
We give details on how to calculate spectral functions and Green's functions for finite systems using the Chebyshev polynomial expansion method. We apply the method to a finite Anderson impurity system, and furthermore give details on how to exploit its symmetry to transform the system into smaller orthogonal subsystems. We also consider systems connected to infinite leads, which we study by approximating the unknown self-energy with an exact self-energy for a finite system. As our test case, we consider the single-impurity Anderson model, where we find that we can capture some aspects of Kondo physics.
Cite
@article{arxiv.1511.00962,
title = {Computing Exact Self-Energies with Polynomial Expansion},
author = {M. Hyrkäs and D. Karlsson and R. van Leeuwen},
journal= {arXiv preprint arXiv:1511.00962},
year = {2015}
}
Comments
10 pages, 6 figures, Part of Progress in Nonequilibrium Green's Functions VI proceedings