Ab Initio Calculation of the (100) and (110) Surface Phonon Dispersion of GaAs and GaN
نویسندگان
چکیده
In this work, we have calculated ab initio the phonon dynamics of the Ga-rich GaAs (100) (1 × 1), GaAs (100) (2 × 1), GaN (100) (1 × 1), GaAs (110) and GaN (110) surfaces. Our results for the (100) surfaces show that, while the (2 × 1) reconstruction is characterized by dimer vibrations, the (1 × 1) reconstruction presents interesting features which is closely related to the reduced mass of the compound. All the studied cases show the presence of a Rayleigh mode. The calculated properties for the (110) surfaces agree very well with the available experimental data from HEELS and inelastic He-atom scattering as well as with other theoretical calculations.
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