Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
5363488 | Applied Surface Science | 2013 | 4 Pages |
We present ab initio calculations of an electronic structure and a topological invariant ν0 of the Ge2Sb2Te5 compound. We have found that in the case of equiatomic composition of Ge/Sb layers the Ge2Sb2Te5 compound is the topological insulator. The ν0 invariant does not depend on a specific location of Ge and Sb atoms in the mixed layers, and depends only on their concentration. The variation of the concentration in the Ge/Sb layers leads to a change of the topological invariant of the compound.
⺠Bulk electronic structure of the ordered compound Ge2Sb2Te5 by full-potential linearized augmented plane wave method. ⺠Ge2Sb2Te5 compound turns into a topological insulator when the layers of mixed composition have equal number of Ge and Sb atoms. ⺠â¤2 topological invariant does not depend on a specific location of the Ge and Sb atoms in the mixed layer. ⺠The â¤2 topological invariant depends only on the concentration of the components in the Ge/Sb mixed layers. ⺠In a realistic Ge2Sb2Te5 crystal the disorder is not expected to affect the existence of the topological state.