Raman-scattering manifestation of a spatial modulation of the order parameter in a NaN02 crystal
Belousov M. V. , Vershovskaya G. Yu. , Kurmanbaev M. S.
The Raman scattering induced by an orientational disordering of N02~ ions has been studied. Upon the transition to an incommensurate phase, the intensity of the Raman scattering by phonons with a wavelength equal to the period of the spatial modulation of the order parameter increases abruptly and then falls off gradually upon a transition to a paraelectric phase.