Two dimensional itinerant magnons in nearly flat topological bands.
- Xiao-Fei Su
- Zhao-Long Gu
- Zhao-Yang Dong
- Shun-Li Yu
- Jian-Xin Li
We study the spin-1 excitation spectra of the flatband ferromagnetic phases in interacting topological insulators. As a paradigm, we consider a quarter filled square lattice Hubbard model whose free part is the