Double light pulses

C Slowing and storage of double light pulses in a Pr YSO crystal... 

Fig. 20. Slowing of double light pulses (a) for the signal-1 and (b) for the signal-2...

Figure 93 Transient photocurrent signals (i) for 8 pm thick Alq3 layers sandwiched between the ITO anode and A1 cathode. Light pulses entered the samples through the ITO anode. The change from the dispersive transport for Alq3 as-received from the supplier (circles) to the non-dispersive transport with purified (squares) Alq3 samples. It can be seen in both linear (a) and double logarithmic (b) plots. In the inset of part (a) electric field dependence of mobility is shown, in part (b) the TOF transient for as-received Alq3 exposed to ambient is added (diamonds). After Ref. 423. Copyright 2003 American Institute of Physics, with permission.

Access to subpicosecond electron pulses has already been achieved at Osaka University by a new double-decker accelerator concept. In order to reduce the time jitter for the detection of the optical absorption signals in pulse radiolysis studies, the light pulse used for the pump-probe system is Cerenkov emission which is produced in the same cell by a synchronized second electron beam and is concomitant with the electron path. The distance between the axes of the two beams is 1.6 mm. The pulse durations of these electron pulses, which are both produced by delayed beams issued from the same laser, are 430 + 25 fs and 510 20 fs, respectively, and the charge per pulse is 0.65 nC. An electron bunch of 100 fs and 0.17 nC has already been generated. 

We have performed optically heterodyne-detected optical Kerr effect measurement for transparent liquids with ultrashort light pulses. In addition, the depolarized low-frequency light scattering measurement has been performed by means of a double monochromator and a high-resolution Sandercock-type tandem Fabry-Perot interferometer. The frequency response functions obtained from the both data have been directly compared. They agree perfectly for a wide frequency range. This result is the first experimental evidence for the equivalence between the time- and frequency-domain measurements. 

The occurrence of double hits and misses (assumption d) was introduced to account for the increasing degree of disorder in S-state distribution as revealed by the damping of 02-yield oscillation in a sequence of flashes. This assumption can equally explain why the maximum yield observed on the third flash is not quite three times the yield obtained in steady state. The extent of double hitting is expected to be related to the duration of the light pulse as compared to the relaxation time of the transitions S -> + the limiting step in the PSII turnover rate. Experiments with... 

We have carried out time-resolved EL measurements of polymer-based light-emitting devices. The transient EL spikes exhibit bi-exponential decay pattern. Temperature independence of the decay pattern allows us to rule out polarization due to polymer matrix relaxation as an EL governing process. According to our interpretation, the phenomenon of double light spikes under pulsed electrical... 

Normal pulsed lasers, chopped cw laser radiation, or mode-locked dye lasers can be used for the generation of the light pulses. The output powers of the cw and mode locked lasers are rather low and they can be applied only in the visible or, after frequency doubling, in the UV spectral region [35]. They can be used for lifetime measurements with high accuracy [36] Only radiation from pulsed lasers can be transformed down to the VUV spectral region by using nonlinear effects. 

Barker et al. [Faraday Disc. Chem. Soc., 56, 41 (1974)] performed experiments in which 15-ns pulses from a frequency-doubled ruby laser were used to illuminate a mercury pool working electrode. Each light pulse caused ejection of electrons from the electrode. Ejected electrons seem to travel about 50 A before becoming solvated and available for reaction. 

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