Elastic waves at the (001) and (110) surfaces of AlN, GaN and InN

Vibrational properties of (0 0 1) III–V nitride superlattices

“…The Green's function elements and their normal derivatives for the case of (0 0 1) interfaces have been given in [20] and will not be repeated here. From these projections and the boundary conditions at the different interfaces (continuity of the displacements and normal stress) we can obtain the interface projection of the Green function of the system e G S [23].…”

“…The elastic constants of these materials have not yet been determined experimentally [18], but several theoretical calculations of the elastic constants exist giving essentially the same trend although different numerical values. The values obtained by means of first-principles method [19] are recommended in [18] and they can be taken as representative, as shown in the study of the surface waves [20], single and multiple wells [21] in these materials. It can be seen that the elastic constants of the III-V nitride are quite different and as a consequence they can exhibit big gaps.…”

Elastic layered waves in (001) III-V nitride systems

“…A calculation by using densityfunctional theory, ab initio pseudopotentials, and plane-wave expansions 31 can be taken as a representative, as shown in the study of the surface waves in these materials. 32 These systems can serve to illustrate in a very general way the behavior of the acoustic waves in multilayer cubic systems including the anisotropy, that to our knowledge has not been considered.…”