0000000000004180
AUTHOR
Isaac Hernández-calderón
Temperature dependence of Raman scattering and luminescence of the disordered Zn0.5Cd0.5Se alloy
Abstract We report on luminescence and Raman scattering measurements of zincblende Zn0.5Cd0.5Se thin film grown by molecular beam epitaxy. From the luminescence data of the exciton peak, the dependence of the energy gap with temperature [ d E g / d T=(4.35±0.01)×10 −4 meV / K ] and zero-temperature phonon renormalization energy ( Δ E(0)=30±1 meV ) have been obtained. The broadening of the excitonic emission as the temperature increases is mainly due to scattering processes with longitudinal optical phonons and residual ionized impurities. Raman scattering shows a multiphonon structure, which depends on the temperature. At low temperatures, up to the fifth-order phonon peaks appear due to re…
Ab initio structural and electronic band-structure study of MgSe
We present a careful and detailed ab initio study of the crystal structure and electronic band structure of different crystalline phases of MgSe. Calculations were performed using the full-potential linear augmented plane wave method. To determine the crystal phase of the ground state of MgSe, we computed the total energy as a function of volume for the rock-salt, zinc-blende, wurtzite, and NiAs phases. From the optimized volume, and by using the Birch–Murnaghan equation of state the lattice parameters , the bulk moduli, and its first pressure derivative () for the different phases of MgSe were found. In our calculations, we have used the local density approach for the exchange–correlation …