Concurrent pump-probe and streak camera measurements with a single mode-locked Nd:YAG laser: A picosecond absorption/emission spectrometer

Abstract

A description is presented of a laser system that can be used for two concurrent and independent types of picosecond spectroscopic measurements. Two data-collection sybsystems, (1) a picosecond pump-probe transient absorption/emission spectrometer and (2) a streak camera system for time-dependent measurements of absorption and emission, have been developed as independent work stations within an integrated system based on a single mode-locked Nd:YAG laser oscillator which concurrently supplies each subsystem with picosecond pulses. The electronic links among the two work stations and the laser are discussed. In addition to applications involving pump-probe absorption and pulsed laser-induced emission measurements, this system can be used for picosecond-pulsed preparation-pump-probe absorption and preparation-pump emission experiments. Examples of data collected with each subsystem are presented to illustrate the complementary nature of the information that can be obtained with this versatile laser system.

Laser Techniques in the Study of Drug Photochemistry¶

“…The fast evolution of events prevents the use of a normal digitizer, where typical sampling rates are at best 2.0 GHz (72). Two approaches are then used to obtain a time and wavelength profile, one requires the use of a streak camera (see above) and the other the use of a two pulse or pump‐probe technique (72,73).…”

The Dual Beam Picosecond Continuum Technique for Measurement of Short-Time-Scale Transmission Spectra

“…Water is used by many researchers to produce the visible spectrum or "white" light, as is heavy water, or D 20 [5][6][7][8]. Using a 1:1 mixture of H 2 0 and D 20, however, is common practice today [2]. This approach takes advantage of the different vibrational energy levels of the two different molecules, so that the Raman lines fill the spectrum more fully.…”

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“…following equations show how a differential transmission value was obtained from the data. First, the intensity of the continuum beam, /0> is split by the beam splitter with some constant function of wavelength near 50%: (2) where [uPo and [do o are the intensities of the upper and lower beams after the split, respectively. Therefore, the ratio of the upper to the lower beam is…”

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