Enhancement of the Scattering Intensity for the Hyper-Raman Effect in Connection with Statistical Properties of the Excitation Light Source

Abstract

Abstract The scattering intensity for the hyper-Raman effect is found to depend on statistical properties of the excitation light source. In close correspondence to the two-photon absorption process also for the hyper-Raman effect there arises an amplification factor of 3/2 up to 2 for the superposition of two or an infinite number, respectively, of incoherent light waves, polarized parallel. This result is derived in semiclassical terms so that the origin of the effect can be followed more clearly than in quantum electrodynamical calculations. It is shown that natural light in nonlinear optics can be represented mathematically alternatively by superposing linearly or circularly polarized light waves as in linear optics, but with the important modification that one should superpose an infinite number of incoherent components instead of only two of them. A new experimental method is proposed to observe the hyper-Raman effect using the mode locking technique. It is shown that the scattering intensity can be increased in this way by a factor of approximately ⅔ M where M is the number of modes coupled together with a constant frequency separation ⊿ω.