Ab initio calculation of elastic constants and electronic properties of ZnSe and ZnTe under uniaxial strain

Abstract:

The second and third order elastic constants of ZnSe and ZnTe, the electronic deformation potentials, and other bulk properties under uniaxial strains are calculated. We used first-principles density-functional theory applied to supercells with the plane wave method and energy cutoffs of 30-40 Ry. The 3d states of Zn were treated as core states but a nonlinear core correction was used for the exchange and correlation energy. We determined the internal strain parameter and calculated the deformation density of unstrained ZnSe with and without Zn-3d valence states. The change of the electron density in ZnSe due to uniaxial strain in [001], [110], and [111] directions is demonstrated. We also present the density of states and the change of the deformation density of bulk ZnTe due to biaxial strain like in a thin epilayer on a GaAs(001) substrate. The change of the density of states is also discussed here. Finally, the Luttinger parameters of ZnSe are calculated.