Magnetic phase diagram of the half-filled t-t'-Hubbard model -- finite-U effects on competing interactions and frustration

2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/18712The magnon propagator is evaluated in the AF (π,π,π) and the F-AF (0,π,π) states at the RPA level, and the spin-fluctuation corrections are compared. Transverse spin fluctuations are sharply enhanced by the frustration- inducing NNN hopping t', reducing the zero-temperature AF order in two dimensions, and the Neel temperature in three dimensions. The phase boundary between the insulating AF and F-AF states is obtained in the full range of interaction strength, indicating that the AF state is interestingly stabilized with decreasing U.8 pagesStrongly Correlated ElectronsMagnetic phase diagram of the half-filled t-t'-Hubbard model -- finite-U effects on competing interactions and frustrationtext