Calculation of Chern number spin Hamiltonians for magnetic nano-clusters by DFT methods
By combining field-theoretical methods and ab initio calculations, we construct an effective Hamiltonian with a single giant-spin degree of freedom, which is capable of describing the low-energy spin dynamics of ferromagnetic metal nano-clusters consisting of up to a few tens of atoms. In our procedure, the magnetic moment direction of the Kohn-Sham spin density functional wave function is constra
