Premium
Polaritons and Phonon Assignment in Orthorhombic KNbO 3 Investigated by Light Scattering
Author(s) -
Winter F. X.,
Wiesendanger E.,
Claus R.
Publication year - 1974
Publication title -
physica status solidi (b)
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.51
H-Index - 109
eISSN - 1521-3951
pISSN - 0370-1972
DOI - 10.1002/pssb.2220640112
Subject(s) - orthorhombic crystal system , phonon , polariton , scattering , raman scattering , spectral line , condensed matter physics , dielectric , phonon scattering , raman spectroscopy , optics , molecular physics , materials science , physics , diffraction , optoelectronics , quantum mechanics
Phonon spectra for the principal directions of orthorhombic KNbO 3 have been recorded by Raman scattering using right angle and back scattering techniques. Assignments of all A 1 and A 2 modes are given and those of B 1 and B 2 modes discussed. Polariton spectra concerning the A 1 and B 1 species recorded by near forward scattering made the assignment of longitudinal B 1 modes possible which were not observed in the phonon spectra. The upper photon‐like B 1 polariton branch has been observed using a photographical arrangement. A comparison is made of the dielectric constants obtained from the phonon frequencies using the Lyddane‐Sachs‐Teller relation with data from the literature.