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arXiv · 2310.02179

Fast Fermion Smearing Scheme with Gaussian-like Profile

ChuanYang Li·Terrence Draper·Jun Hua·Jian Liang·Keh-Fei Liu·Jun Shi·Nan Wang·Yi-bo Yang
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Abstract

We propose a novel smearing scheme which gives a Gaussian-like profile and is more efficient than the traditional Gaussian smearing in terms of computer time consumption. We also carry out a detailed analysis of the profiles, smearing sizes, and the behaviors of hadron effective masses of different smearing schemes, and point out that having a sufficient number of gauge paths in a smearing scheme is essential to produce strong smearing effects. For a moderate smearing size $\bar{r}\sim 10a$, the time cost for the novel smearing is less than $1/8$ of that for the traditional Gaussian smearing. In practical lattice calculations with larger smearing sizes or finer lattice spacings the improvement will be more substantial.

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ChuanYang Li, Terrence Draper, Jun Hua, Jian Liang, Keh-Fei Liu, Jun Shi, Nan Wang, Yi-bo Yang. 2023-10-03. Fast Fermion Smearing Scheme with Gaussian-like Profile. https://arxiv.org/abs/2310.02179

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