Single Molecules Driven by Strong Resonant Fields: Hyper-Raman and Subharmonic Resonances

Abstract

We present pump-probe experiments on single molecules in a solid matrix, with strong laser fields and a new host-guest system, dibenzanthanthrene in a naphthalene crystal. Besides strong light-shifts of the lines, we observe the hyper-Raman resonance, for the first time in condensed matter. For strong pump and probe, we also observe subharmonic resonances due to a”kicked pendulum” motion of the Bloch vector. Since our results agree with Bloch's equations without any adjustable parameter, they provide a stringent test of the optical two-level model as applied to single molecules in solids.