Optical pulse circularly polarized

Photoderacemization is the simplest case of direct asymmetric photoreactions induced by cpl. The enantiomers are interconverted, and the mixture becomes optically active. Reaction scheme 2 is a modification of Scheme 1 ground state racemization is excluded. The enantiomerization step R S was observed directly by Metcalf et al. [9] by means of the time-resolved circularly polarized luminescence of europium-tris(bipicolinate). By means of a cpl laser pulse, a difference in the excited state population is created, and the decay of circular... 

The method takes advantage of an excite and probe technique with polarization selective detection. A circularly polarized pxnnp pulse of ps duration generates a coherent superposition of atomic substates. The coherence induces an optical anisotropy in the atomic sample, which oscillates exactly with the splitting frequency of the respective substates. 

If a second delayed pulse with circular polarization and wave vector k2 acts on the atoms at time t2, it generates new optical coherences, e.g,... 

The experimental set-up we used is shown in Fig. 2, A synchronously pumped mode-locked and cavity-dvunped dye laser, which can be timed to the D or Dj line of Cs, generates pulses of about 20 ps duration at a pulse rate of U MHz and peak powers of several hundred watt. They are split into linearly polarized pump pulses and stronger circularly polarized probe pulses, which pass an optical delay line. Both beams are focussed into a common interaction region where they act on the Cs vapor, which is contained in a cell at room temperature. The radiated wave propagating in pump pulse direction is detected by a photomultiplier, which measures the transmitted average intensity behind a crossed polarizer as a function of the delay time. 

A/2 wave plate. The other beam passes through the other acousto-optic modulator that is used to turn on and off the laser to generate the probe pulse. The focus length of LI, L2, L3, and L4 is 5cm. The two beams are eombined with a polarizing beam splitter. Then they are changed to opposite circularly polarized beams with a A / 4 wave plate. We perform the experiment in... 

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