Optical study of the Mott transition in V2O3: Comparison of time- and frequency-domain results

We report the results of an optical study of the Mott transition in V2O3 ca rried out by time- and frequency domain spectroscopies. We have observed ti me-resolved spectra through the Mott transition with oscillations in reflec tivity associated with the fully symmetric modes. As a consequence of the p hase transition, the Raman spectrum also shows an abrupt change of both the phonon and electronic excitations. Most notable are (i) disappearance of t he electronic continuum, which is very strong and broad in the metallic sta te, and (ii) altered coupling of a fully symmetric phonon to the electronic subsystem, which is shown to be temperature dependent even above the trans ition. We notice that although the spectra obtained by the time- and freque ncy-domain spectroscopies are similar, there are distinct differences in ph onon line shape. [S0163-1829(98)04743-2].