Sonstationary ltaman-Induced Herr Effect in Liquids and Uniaxial PiezocrystalvS b s t r a c t . A nonstationary probe-beam method using Baman-induced Kerr effect (RIKE) for ineasuring the (transversal) relaxation constant 1'( = TT') of piezo crystals and Raman active liquids is disc~~ssed. T n isotropic media, in every scattering geometry phase matching is realised automatically for all frequencies and therefore, in contrast to coherent act.ive Raman spectroscopy (CARS), the complete Raman spectrum is generated simultaneously and also its time behavionr can be studied. (In anisotropic crystals the appearing of RIKE will bc drastically reduced.)For arbitrary corrclation bchaviour of the pump fields the nonstationary signal intensity vanishes exponentially with the effective vibration damping constant and with the delay-time of the testpulse. The dependence of the signal on the characteristic interaction length betwcen the pulses (L,s), on the phase modulation times T , , , ,~, and on the probe length L arc studied. The malogies between the methods of active Itaman spcctroscopy (AHS), RIKIS, and induced two-plioton-emission-cxperiments will be illustrated.
EinleitungRei der gleichzcitigen Ucstrahlung cines ra.manaktiven Medium niit einer zirlrular polarisierten I'umplaserwelle (Frequenz oL) und eineni linear polarisierteri St.okes ( w ,~) -(oder auch Antistokes-)Kontinuum verursacht die nichtlineare Wechsclwirkung der Felder irii Mediuiii die Entstehung einer neuen Stokes-~eldkomponente, die senlrrecht zur urspriinglichen Stolreswelle polarisiert, ist irnd Hesonanzohnraktcr bcsitzt, wenn