A planar force-constant model for phonons in wurtzite GaN and AlN: Application to hexagonal GaN/AlN supperlattices
نویسندگان
چکیده
A planar force-constant model is developed for longitudinal phonons of wurtzite GaN and AlN propagating along the [0001] direction. The proposed model is then applied to the study of the phonon modes in hexagonal (0001)GaN/AlN supperlattices in longitudinal polarization. The confinement of the superlattice phonon modes is discussed. PACS numbers: 68.20.Dj, 68.35.Ja Typeset using REVTEX
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