Time-resolved interferometry

C. Fauquignon stated that a similar use of microwaves in time resolved interferometry was developed in the laboratory of the Commissariat de I linergie Atomique, France (p 594)... 

Figure 1. Time-resolved interferometry system. A 248 nm or SSlnm excimer laser pulse (fwhm 30 ns) as as excitation light and a 532 nm pulse (fwhm 10 ns) as an probe light are irradiated to a sample film. Abbreviations are PD photodiode, OS oscilloscope, BS beam splitter, PG pulse generator. A attenuater, L lens, M mirror, BPF band pass filter.

Minoshima, R., Taiji, M., and Kobayashi, T., Femtosecond time-resolved interferometry for the determination of complex nonlinear susceptibility. Opt. Lett., 16, 1683-1685 (1991). 

Scherer N F, Carlson R J, Matro A, Du M, Ruggiero A J, Romero-Rochin V, Cina J A, Fleming G R and Rice S A 1991 Fluorescence-detected wave packet interferometry time resolved molecular spectroscopy with sequences of femtosecond phase-locked pulses J. Chem. Rhys. 95 1487... 

Grosso, D. Babonneau, F. Albouy, P. A. Amenitsch, H. Balkenende, A. R. Brunet-Bruneau, A. Rivory, J. 2002. An in situ study of mesostructured CTAB-silica film formation during dip coating using time-resolved SAXS and interferometry measurements. Chem. Mater. 14 931-939. 

Scherer, N.F., Carlson, R.J., Matro, A., Du, M., Ruggiero, A.J., Romero-Rochin, V., Cina, J.A., Fleming, G.F. and Rice, S.A. (1991) Fluorescence-detected wave packet interferometry - time resolved molecular-spectroscopy with sequences of femtosecond phase-locked pulses. 

TIME RESOLVED INFRARH) INTERFEROMETRY, Part 1, D. E. Honigs, R. M. Hammaker, W. G. Fateley, and J. L. Koenig... 

Figure 15. Time resolved infrared absorption spectra of Vs(N02) in 940 nm thick PVN films during shock loading, in reflectance units. Calculated plots include only thin film interference effects, excluding pressure and temperature shifts and chemical reaction, making the differences between the experimental and calculated spectra the primary subjects of interest. Shock pressures were determined by interferometry. Arrows show the time at which the shock has fully traversed the film and rarefaction begins.

The analysis of the transmission of the film during irradiation suggests that decomposition of the triazene chromophore occurs during irradiation. The decomposition of the chromophore in the film should result in changes of the surface topography. Therefore another time-resolved method was applied that can give this information. This technique is nanosecond interferometry, which allows the observation of the surface morphology with nanosecond resolution. 

Transition radiation is considerably weaker than Cerenkov radiation, however since it is a surface phenomenon it avoids problems with radiator thickness and reflections inherent to Cerenkov-generating silica plates. Optical TR can be measured using a streak camera. An optical TR system has been used to time-resolve the energy spread of an electron macropulse in a free-electron laser facility [10]. Interferometry of coherent, far-infrared TR has been used to measure picosecond electron pulse widths and detect satellite pulses at the UCLA Satumus photoinjector, using charges on the order of 100 pC [11],... 

Time-resolved Spectroscopy Finally in this section, the advent of step-scan interferometers has opened up exciting opportunities to study fast, reversible surface processes. Details on step-scan interferometry may be foxmd elsewhere [144] briefly in conventional mode (see in previous text), the mirror moves essentially continuously, with intensity measurements taken at regular intervals (Fig. 12). In step-scan mode, the mirror is paused at each position (retardation), allowing the exploitation of the time-resolved spectroscopy option ofthe spectrometer. Once the mirror has settled at a particular position, a reference point can be taken, after which a reaction can be triggered, that is via a light pulse or potential step, and the intensity measured at regular intervals (Fig. 13). 

In addition to the substantial literature on solvent and small-molecule translational diffusion, there is also a significant literature on small-molecule rotational diffusion. Experimental methods that report rotational diffusion behavior include VH tight scattering, as examined in different time domains with Fabry-Perot interferometry and photon correlation methods, nuclear magnetic resonance, oscillatory electrical birefringence, and time-resolved optical spectroscopy. 

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