CARS-Background suppression by phase-controlled nonlinear interferometry

Abstract

We have developed a new technique for efficient suppression of the nonresonant background in coherent anti-Stokes Raman scattering (CARS). The advantage of this technique, which is based upon phase-controlled superposition of an appropriately selected reference signal, is presented in theory and demonstrated experimentally by the example of the S(3) (pure rotational) transition of molecular hydrogen.