Electronic properties of Mn-decorated silicene on hexagonal boron nitride

We study silicene on hexagonal boron nitride, using first-principles calculations. Since hexagonal boron nitride is semiconducting, the interaction with silicene is weaker than for metallic substrates. It therefore is possible to open a 50 meV band gap in the silicene. We further address the effect of Mn decoration by determining the onsite Hubbard interaction parameter, which turns out to differ significantly for decoration at the top and hollow sites. The induced magnetism in the system is analyzed in detail.

Figure 1

(a) Electronic band structure and (b) charge transfer for silicene on a bilayer of BN (side view). The isosurfaces correspond to isovalues of $\pm 5\times {10}^{-4}$ electrons/Å${}^3$. The black, blue, and red spheres denote Si, N, and B atoms, respectively. Red and blue isosurfaces refer to positive and negative charge transfer. Note the significant charge transfer of the Si closest to the BN.

Figure 2

The spin density map for silicene decorated by Mn at the (a) top and (b) hollow site of the $h$-BN substrate. The hollow site is energetically favorable.

Figure 3

Total (left) and Mn partial (right) densities of states of silicene decorated by Mn at the (a) top and (b) hollow site of the $h$-BN substrate.