COHERENT AND INCOHERENT DUAL-FREQUENCY OPTICAL SPECTROSCOPY: APPLICATIONS TO GAS PHASE COLLISIONAL DYNAMICS.
Summary form only given. The authors present work with coherent and incoherent dual-frequency experiments designed to measure detailed microscopic collisional dynamics in molecular gases. In the incoherent version, a laser pulse sequence consisting of two 180 degree pulses (each 100 ns long) is applied. Each pulse has a bandwidth such that only a narrow range of velocities in the Doppler profile is excited. As both pulses are 180 degree and not phase specific, this incoherent experiment measures population transfer between velocity ranges. In the coherent version both pulses are 90 degree and phase specific, so the experiment measures collisional effects on phase memory.