Function QCM::get_combined_mcf_k

Function Documentation

ED::CombinedMCF_data QCM::get_combined_mcf_k(const vector3D<double> &k, bool spin_down, int label)

Returns the combined MCF (W, A[j], B[j]) periodized into the band basis at wavevector k.

Returns the combined matrix continued fraction (W, A, B) for the cluster Green function at k.

Implements the ‘L’ periodization scheme: adds inter-cluster hopping V to A[0], applies compact_tiling to A[j>=1] and B[j>=1], then periodizes all blocks and W. Only valid with a single cluster per lattice model and with GF_method=’M’ or GF_method=’L’ + combine_mcf=True.

Parameters:

  • k – wavevector in the physical reciprocal basis (same convention as periodized_Green_function)

  • spin_down – true for the spin-down sector (mixing = 4)

  • label – lattice model instance label