Portal de Periódicos da CAPES

Light Scattering Spectra Depending on the Direction of Scattering Wave Vector in KD 2 PO 4 . I Brillouin Spectrum and Broad Central Component

1979; Physical Society of Japan; Volume: 47; Issue: 6 Linguagem: Inglês

10.1143/jpsj.47.1860

1347-4073

Munehiko Sawafuji, Masaharu Tokunaga, Itaru Tatsuzaki,

Optical and Acousto-Optic Technologies

The Brillouin and Rayleigh scattering spectra have been observed near the transition temperature T c in the paraelectric phase of KD 2 PO 4 as a function of the direction of the scattering vector q in several scattering geometries. The broad central component ascribed to dynamical spectrum of the Debye type relaxational mode by Reese et al. has been studied in both the ab - and the ac - scattering planes. Theoretical formulas are derived to explain q and temperature dependences of the intensity of the broad central spectrum. The frequency of the acoustic mode coupled with this mode is found not to decrease even near T c in the wave-length region of the Brillouin scattering. The q dependence of the Brillouin scattering intensity has been measured and can be accounted for by the fundamental theory mentioned above.