Differential Second-Order Raman Spectroscopy

Abstract

It is shown that measurement of the derivative of the second-order Raman spectrum with respect to wavelength of the scattered light gives information on the Van Hove critical points of the combined two-phonon energy function. The results of such a measurement on SrTi${\mathrm{O}}_{3}$ at 10\ifmmode^\circ\else\textdegree\fi{}K are presented and discussed.