Ideal CdTe/HgTe superlattices
نویسنده
چکیده
In this paper we consider a new superlattice system consisting of alternating layers of CdTe and HgTe constructed parallel to the (001) zincblende plane. The tight-binding method is used to calc~late the electronic properties of this system, in particular, band edge and interface properties. The energy gap as a function of layer thickness is determined. It is found to decrease monotonically with increasing HgTe layer thickness for a fixed ratio of CdTe to HgTe l~yer thicknesses. !he symmetry of the valence band maximum state is found to change at certam HgTe layer thicknesses. This is explained by relating the superlattice states to bulk C?Te and HgTe states. The existence of interface states is investigated for the superlattice With 12 layers of CdTe alternating with 12 of HgTe. Interface states are found near the boundaries of the Brillouin zone, but none are found in the band gap.
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