Raman scattering of polar materials


The main scope of our research is to understand lattice and vibrational dynamics of polar materials, like ferroelectrics, relaxors, biological macromolecules, etc., which are usually probed with laser beam as a function of temperature, under external electric field, and pressure. The main focus is on critical dynamics related to ferroelectric and other relaxation-like phase transitions in ferroelectrics and relaxors, studying temperature- and frequency-dependent soft modes and relaxations in the vicinity of phase transitions. Other topics studied within this research area cover e.g. lattice-mode-coupling phenomena in ferroelectrics, local modes in strongly anharmonic crystals, and geometric resonances coming from ferroelectric domain structure in domain-engineered ferroelectrics. 

Intensity maps of Raman spectra of PSN
Intensity maps showing the dependence of Raman spectra of a PbSc1/2Nb1/2O3 thin film on the angle between the transmission direction of the analyzer and one of the in-plane pseudocubic axes of the film. Left panel (a) corresponds to cross-polarized geometry while the right panel (b) corresponds to the parallel-polarized geometry.


Theme is contributed to by