Zone-center optical phonons in wurtzite InAlN crystal

An experimental study of the optical phonons is presented for InAlN epilayers lattice-matched with GaN by means of Raman scattering, and theoretical simulations are done to investigate the zone-center optical phonons of InAlN alloy by using the modified random element isodisplacement (MREI) model. The calculated findings show that the LO and TO branches of InAlN crystal both exhibit nonlinear properties. A comparison is made between the theoretical results and the experimental data, and it shows that they are both consistent for the A1(LO) phonons of InAlN epilayers.