Portal de Periódicos da CAPES

Ab initio calculation of the linewidth of various phonon modes in germanium and silicon

2003; American Physical Society; Volume: 67; Issue: 14 Linguagem: Inglês

10.1103/physrevb.67.144304

1095-3795

Gernot Deinzer, G. Birner, D. Strauch,

Mechanical and Optical Resonators

The $2n+1$ theorem and the density-functional perturbation theory have been used to calculate anharmonic force constants completely ab initio. Explicit expressions for the anharmonic coupling constants are presented, i.e., for the third-order derivatives of the total energy with respect to atomic displacements. Using the harmonic as well as the anharmonic results the phonon linewidth of Ge and Si as a function of temperature has been calculated for various branches and various (in particular, for nonvanishing) wave vectors completely ab initio.