Structural and elastic properties of strained Mg1−xSrxSe revealed

For the first time, detailed first principle calculations within the generalized gradient approximation (GGA) are performed to study electronic structure and elastic properties of Mg 1 − x Sr x Se ternary alloys at various concentrations of Sr atoms. Band gap energies are predicted for the ternary alloys with x=0.47 concentration to have a minimum energy gap of 2.07 eV. From our calculations the alloy closely follows Vegardʹs law with a small bowing parameter of −0.0103 Å. Calculated elastic constants are given along with other elastic properties for the ternary alloys. Among the examined structures, Sr-rich alloys display a large Poissonʹs ratio indicating a stretch densifying property. The resemblance of the calculated lattice parameter at low Sr concentration to that of InAs suggests that MgSrSe alloys can be experimentally grown on indium arsenide.