Open AccessRaman opalescence near the phase transition point in lead germanate crystals
Author(s) -
A. Yu. Pyatyshev,
В. С. Горелик
Publication year - 2019
Publication title -
journal of physics. conference series
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.21
H-Index - 85
eISSN - 1742-6596
pISSN - 1742-6588
DOI - 10.1088/1742-6596/1348/1/012061
Subject(s) - opalescence , germanate , phase transition , raman spectroscopy , materials science , crystal (programming language) , soft modes , raman scattering , radiant intensity , softening , condensed matter physics , lattice (music) , radiation , optics , molecular physics , chemistry , physics , optoelectronics , doping , computer science , dielectric , acoustics , composite material , ferroelectricity , programming language
It was established that the nature of opalescence near the phase transition point in a lead germanate crystal is dynamic and is caused by a sharp increase in the spectral intensity of Raman scattering on a soft mode responsible for the instability of the crystal lattice near the phase transition temperature. Experimental studies of combination opalescence in a soft mode were performed using the method of constructing isofrequency temperature dependences of the spectral intensity for fixed values of the frequency shift Ω of the scattered radiation relative to the frequency ω 0 of the exciting radiation. It is shown that the experimentally observed anomalies of the spectral intensity agree with the dynamic theory of phase transitions in crystals, based on the concept of softening of the crystal lattice in the phase transition region.