PYED + VCA: Exact diagonalization of finite quantum systems with variational cluster approximation

The software package was developed that implements the variational cluster approximation for solving the generalized Hubbard model taking into account systems of various dimensionality, with several orbitals, and various lattice geometries. The developed package was tested on the one-band Hubbard model; antiferromagnetic ordering and the superconducting phase were observed, in accordance with known results obtained by other techniques. The resulting code may be successfully used for studying properties of high-temperature superconductors.