Adiabatic Spin Wave Dynamics in Strongly Correlated Itinerate systerm

In 1998, Niu and Kleinman proposed an adiabatic spin-wave dynamics theory for ab initio calculations of spin-wave excitations. This formalism decouples spin and charge excitations under the adiabatic approximation. Once the energies and Berry curvatures of the states corresponding to frozen spin waves are obtained, the equations of motion for the spin waves can be constructed. However, when evaluating the Berry curvatures, if the frozen spin-wave states are generated using strongly correlated methods rather than the Hartree–Fock approach, the resulting description can better capture strong interaction effects that are absent at the Hartree–Fock level. In this work, we combine the adiabatic spin-wave dynamics theory with the slave-boson method and apply the resulting framework to the Hubbard model. Our results show that the spin-wave dynamics obtained from this approach agree more closely with determinant quantum Monte Carlo (DQMC) results compared with the random-phase approximation (RPA), indicating that our method provides a more accurate treatment of strong correlation effects.