ThetaPhi - a new program for calculation of Bardeen-Cooper-Schrieffer and Magnetic Superstructure Electronic States

We propose the Theta-Phi package [1] which addresses two of the most important extensions of the essentially single-particle mean-field paradigm of the computational solid state physics: the admission of the Bardeen-Cooper-Schrieffer electronic ground state and allowance of the magnetically ordered states with an arbitrary superstructure (pitch) wave vector. Both features are implemented in the context of multi-band systems which paves the way to an interplay with the solid state quantum physics packages eventually providing access to the first-principles estimates of the relevant matrix elements of the model Hamiltonians derived from the standard DFT calculations. Several examples showing the workability of the proposed code are given.
[1] E. Plekhanov, A. Tchougreeff, R. Dronskowski arXiv:1812.11632v2