Optics Letters

Coherent versus incoherent Raman scattering: molecular coherence excitation and measurement

Dmitry Pestov, Gombojav O. Ariunbold, Xi Wang, Robert K. Murawski, Vladimir A. Sautenkov, Alexei V. Sokolov, Marlan O. Scully

Published Jun 6, 2007• 66 citations

Publisher

Abstract

We present a comparative analysis of spontaneous and coherent Raman scattering on pyridine. The instantaneous excitation of the molecular coherence is done by a pair of ultrashort preparation pulses. Then, a long narrowband probe pulse is scattered off the molecular vibrations. The described hybrid technique allows for the single-shot acquisition of a background-free coherent Raman spectrum within the excitation band and its straightforward comparison with the spontaneous Raman measurements, performed in the same setup. We report a 10(5)-fold increase in the efficiency of the Raman scattering process due to the broadband pump-Stokes preparation. The coherence magnitude (approximately 0.5x10(-3)) is inferred experimentally, without a priori knowledge about the molecular structure.

DOI: 10.1364/ol.32.001725

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