Far-Infrared Dielectric Function of Zincblende ZnS
نویسنده
چکیده
The complex dielectric response function of zincblende ZnS is determined a t 300 K by dispersive Fourier transform spectroscopy. The frequency range studied, 150 to 450 cm-l, spans the frequency of the q = 0 transverse optic (TO) phonon mode. The frequency dependence of the anharmonic self-energy function T(Y) of the q = 0 TO phonon is calculated from these data. The features observed in the spectrum of T(Y) are satisfactorily assigned to multi-phonon processes by comparison to theoretical lattice dynamics calculations for cubic ZnS.
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