Computing Local Multipoint Correlators Using the Numerical Renormalization Group

@article{Lee2021ComputingLM,
  title={Computing Local Multipoint Correlators Using the Numerical Renormalization Group},
  author={Seung-Sup B. Lee and Fabian B. Kugler and Jan von Delft},
  journal={Physical Review X},
  year={2021}
}
Local three- and four-point correlators yield important insight into strongly correlated systems and have many applications. However, the non-perturbative, accurate computation of multipoint correlators is challenging, particularly in the real-frequency domain for systems at low temperatures. In an accompanying paper, we introduce generalized spectral representations for multipoint correlators. Here, we develop a numerical renormalization group (NRG) approach, capable of efficiently evaluating… 
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