Light pulse Gaussian

Figure 8.1 (a) Block diagram of the femtosecond near-infrared laser microscope system, (b) Spectrum ofthe light pulse from the Cr F laser, (c) Interferometric autocorrelation trace of SHG signal with envelope curve calculated assuming a chirp-free Gaussian pulse with 35 fs fwhm. 

Figure 1.64. Normalized fast component of the photocurrent in oriented Omham trans- C )x excited with 25 ps lasser pulses (532 nm) at room temperature. The energy of the incident light pulses with polarization perpendicular to the stretch direction is 0.95 / J at a sample area of 200 /xm 300 /xm. The integral under the peak corresponds to 1.5 x 10 electronic charges (17o = 100 V). The solid line represents the best fit to the curve obtained by convoluting the photoconductivity response with the overall system response (assumed to be Gaussian). (Reprinted with permission from ref. 149)...

Figure 3.13a-c shows the output pulse waveform from GI POFs with microscopic heterogeneities, with microbending, and without any perturbations, calculated for different fiber lengths. The temporal pulse shape of the incident light is Gaussian with a full width at half-maximum of 83 ps. Owing to intermodal... 

The first 15 wave functions were used in a dynamical simulation of the Liouville equation for the density operator. The Franck-Condon factors were generated by assuming that the ground-state vibrational wave function is a Gaussian centered at —1 A, with a width of 0.1 A. The central frequency of the light pulse was chosen... 

Figure 9.11 Proton density in the double well shown in Figure 9.10 at 10-fs intervals starting at 10 fs after a 15-fs Gaussian light pulse. The dashed lines indicate the position of the wells. It is obvious that a probe...

In the quasi-statie approximation, Eq.(2.9) has been solved numerieally by the FD-BPM for eaeh stationary eomponent of temporal distribution of the light beam. Amplitudes of the stationary eomponents were speeified by the form of pulse temporal envelope. The initial pulse envelope was assumed Gaussian. 

The spectrum in Fig. 8(b), shows the effect of a pulse width reduction to 9 ns. This spectrum represents the conditions under which the actual fluorescence lifetime measurements were performed. Due to the shorter pulse duration, the spectral width of the excitation light severely broadens the molecular resonances. In this case typical linewidths of 75 MHz were observed. Fitting again the profile of molecule C, the best results were obtained using a Gaussian lineshape with a FWHM of 73 MHz. The resonances of molecules A and B are separated by 60 MHz. In spectrum (a) both resonances are clearly resolved. At a pulse duration of 9 ns both peaks cannot be distinguished any more so that both molecules are not suitable for the individual fluorescence lifetime measurements (spectrum 8b). Molecules C and D are ideal candidates, since they are clearly resolved and do not overlap even at 9 ns pulse duration. 

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