We report optical measurements (photoluminescence, Raman scattering, and infrared reflectance) of direct band gap and of optical phonon energies of BexZn1-xSe alloys grown by MBE on (001) GaAs substrates for a wide range of Be concentrations. The high band gap of BeSe (5.15 eV) suggests the possibility of using isoternary alloys for ultraviolet optoelectronic applications. BexZn1-xSe has the unique advantage that it can be lattice matched to Si at about x=0.5. We observed a strong linear shift of the BexZn1-xSe direct band gap to higher energies with increasing Be content (to 3.63 eV for x =0.34). Furthermore, optical phonon parameters for the entire range of BeSe content have been obtained. Finally, polarized infrared and Raman spectra revealed local atomic ordering (anti-clustering) effects in the group-II sublattice.
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Atomic and Molecular Physics, and Optics
- Condensed Matter Physics