Electronic structure of the quantum spin Hall parent compound CdTe and related topological issues

Cadmium telluride (CdTe), a compound widely used in devices, is a key base material for the experimental realization of the quantum spin Hall phase. We report herein a study of the electronic structure of CdTe by angle-resolved photoemission spectroscopy from well-ordered (110) surfaces. The results are compared with first-principles calculations to illustrate the topological distinction between CdTe and a closely related compound HgTe. Through a theoretical simulation a topological phase transition as well as the Dirac-Kane semimetal phase at the critical point was demonstrated in the mixed compound HgxCd1-xTe.