The temperature dependence of the raman effect in some wurtzite type crystals

Abstract

The temperature dependence of the one phonon Raman spectra of ZnS (hex.), ZnO and a-Sic crystals is studied over the temperature range 15 to 1000 K. For ZnS frequency shifts are calculated by Griineisen theory and the k = 0 longitudinal and transverse optic phonon Griineisen parameters determined. The results are compared with existing calculations and where available pressure measurements. Above room temperature the line-widths A q increased approximately linearly for all crystals with temperature, indicating that the principal interactions are the cubic anharmonicities. Various calculated properties include the area, second moment, and simulated Raman bands to illustrate the anharmonic behaviour in the solids.

Structural and optical analysis of ZnBeMgO powder and thin films

“…Both A 1 and E 1 modes are Raman as well as infrared active. The nonpolar E 2 modes have two frequencies, namely, E 2 (low) and E 2 (high) associated with the motion of zinc (Zn) sublattices and oxygen (O) atoms, respectively [31]. Fig.…”

Structure and ferromagnetic properties of Co-doped ZnO powders

“…The nonpolar E 2 modes have two frequencies, namely, E 2 (high) and E 2 (low) associated with the motion of oxygen (O) atoms and zinc (Zn) sublattice, respectively [21]. Fig.…”

Structural and spectroscopic analysis of wurtzite (ZnO)1−x(Sb2O3)x composite semiconductor

“…One of the sharp and remarkable peaks at 436 cm À 1 was detected for all samples and assigned as E 2 (high) mode. This is the strongest mode in wurtzite crystal structure and is due to the motion of oxygen atoms in ZnO lattice [25]. The location of the E 2 (high) mode shows no obvious change with increase in Sb contents, but intensity enhanced with Sb doping level.…”