Abstract
We propose an adaptive scheme of broadening the discrete spectral data from numerical renormalization group (NRG) calculations to improve the resolution of dynamical properties at finite energies. While the conventional scheme overbroadens narrow features at large frequency by broadening discrete weights with constant width in log-frequency, our scheme broadens each discrete contribution individually based on its sensitivity to a z-shift in the logarithmic discretization intervals. We demonstrate that the adaptive broadening better resolves various features in noninteracting and interacting models at comparable computational cost. The resolution enhancement is more significant for coarser discretization as typically required in multiband calculations. At low frequency below the energy scale of temperature, the discrete NRG data necessarily needs to be broadened on a linear scale. Here we provide a method that minimizes transition artifacts in between these broadening kernels.
Item Type: | Journal article |
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Faculties: | Physics |
Subjects: | 500 Science > 530 Physics |
ISSN: | 2469-9950 |
Language: | English |
Item ID: | 47572 |
Date Deposited: | 27. Apr 2018, 08:13 |
Last Modified: | 07. May 2024, 17:38 |