"NRG Ljubljana" - open source numerical renormalization group code
Zitko, Rok. (2021, May 29). NRG Ljubljana (Version 8f90ac4). Zenodo. http://doi.org/10.5281/zenodo.4841076
The package should work unmodified on any modern Unix (MacOS is fine) or Linux distribution with a good standards-compliant C++ compiler (C++17 required, mostly tested with GCC 9.3.0). It requires BLAS/LAPACK libraries, Boost, GNU Scientific Library (GSL), GNU Multiple Precision library (GMP), HDF5 (optionally) and Wolfram Mathematica. Mathematica is only required for the initialization of the problem (basis construction, diagonalisation of the initial Hamiltonian, transformations of the operator matrices, etc.); if Mathematica is not present, the code will still work with manually generated input files.
Legacy versions are documented here.
NRG UFU/2019 Advanced Studies School, in Feb 2019 in Uberlândia, Brazil.
A Mathematica implementation of the NRG method is also available. It illustrates the main ideas of the algorithm on the single-impurity Anderson model using simple Mathematica notebook interface. It calculates the thermodynamic quantities and the expectation values of arbitrary local operators.