Long-Wavelength Optical Phonons In Ternary Nitride-Based Crystals

Phonon modes in column-III-nitride ternary semiconductors an investigated theoretically within the modified random-element isodisplacement model. It is found that A(1) and E-1 branches of optical phonons in wurtzite GaxAl1-xN and InxGa1-xN exhibit one-mode behavior. This result is explained by the fact that atomic mass of nitrogen is much smaller than those of other atoms. [S0163-1829(98)05447-2].