Edge magnetism in triangular silicene quantum dots

The interplay among electron-electron and intrinsic spin-orbit interactions (ISOI) at the zigzag edge of triangular quantum dots (ZTQDs) was analyzed by means of the mean-field Kane-Mele-Hubbard model. It was shown that the magnetic anisotropy (in-plane and out-of-plane magnetic configurations) significantly modifies electronic and magnetic properties of ZTQDs. The in-plane configuration is more energetically stable than the other one. However, its magnetization becomes easier depolarized as a continuous function as strengths of electric field E and ISOI increase. This is in contrast to the out-of-plane magnetization, which is more robust and becomes depolarized in a step-like way. Moreover, the energy gap only vanishes in the out-of-plane case by adjusting E and ISOI strengths, and thus we cannot expect a topological insulator phase in the in-plane magnetic configuration.