Fig. 3: Allowed interactions for two coincident patches.
From: Altermagnetism from coincident Van Hove singularities: application to κ-Cl
a–f The exchange interaction g1, inter-patch Hubbard interaction g2, pair-hopping interaction g3, intra-patch Hubbard interaction g4, and the new hopping interaction g5. Here, upper propagators are for spin-up, while lower ones are for spin-down. Solid& dashed lines label bands 1 and 2.
