Abstract:
We report on the evolution of the Raman-active A(g) phonon modes in the charge-ordered manganite Pr0.63Ca0.37MnO3 as a function of temperature from 300 K to 25 K. Our studies reveal that the linewidths of the A(g)(2) and A(g)(4) phonons increase as temperature decreases. This anomalous temperature dependence of phonon lineshapes, seen for the first time in charge-ordered manganites, can be quantitatively understood in terms of a strong spin-phonon coupling involving t(2g) spins and A(g) phonons.
