First Biennial African Conference on Fundamental Physics and Applications

The effect of Dynamic Jahn Teller interaction on the Raman peaks in manganites

Not scheduled

20m

Auditorium 1, Brahms Street (Namibia University of Science and Technology)

Oral Presentation Material Physics Material Physics

Speaker

Dr A. K Sahu (Seemanta Engineering College)

Description

We report here a microscopic theoretical model showing the influence of dynamic Jahn-Teller (J-T) distortion on the Raman active excitation peaks in the CMR manganite systems. This model Hamiltonian for the system consists of J-T distortion in e_g band, the double-exchange interaction and the Heisenberg spin-spin interaction among the core electrons. Further the phonons are coupled to e_g band electrons, J-T distorted e_g band as well as the double exchange interaction. The phonon Green’s function is calculated by Zubarev’s double time Green’s function technique. The Raman spectral intensity is calculated from the imaginary part of the phonon Green’s function. The intensity exhibits three Raman active peaks. The effect of dynamic Jahn-Teller coupling on these peaks is discussed.