ELECTRONICALLY NONRESONANT COHERENT RAMAN-SCATTERING USING INCOHERENT-LIGHT - 2 BROWNIAN OSCILLATOR APPROACHES

The theory for electronically nonresonant coherent Raman scattering us ing incoherent light (I-(2)CRS) is presented for a Brownian oscillator material response. The exploration of Raman Line shapes is based on t wo different approaches, both of which incorporate the Brownian oscill ator model. The first takes the Raman transition as a two-level system that is indirectly coupled to the bath through ''primary'' Brownian o scillators. The I(2)CRS signal in the overdamped, high temperature reg ime is calculated analytically using this approach. The second approac h is the standard one in which the Raman transition itself is represen ted by primary Brownian oscillators that are directly coupled to the b ath; This method permits analytic calculation of the I(2)CRS signal fo r the entire parameter space and also for a distribution of oscillator s to account for inhomogeneous Linewidth broadening. These two methods allow for different interpretations of Raman line shapes using noisy light spectroscopy. (C) 1998 American Institute of Physics.