Layered Kagome Compound Na${}_2$Ni${}_3$S${}_4$ with Topological Flat Band

Junyao Ye, Yihao Lin, Haozhe Wang +4

We report structural and electronic properties of Na${}_2$Ni${}_3$S${}_4$, a quasi-two-dimensional compound composed of alternating layers of [Ni${}_3$S${}_4$]${}^{2-}$ and Na${}^{+}$. The compo…