Synchronously-pumped mode-locked

The time-resolved Raman spectra were measured with a picosecond time-resolved Raman spectrometer which employs a standard pump-probe technique. The details of the spectrometer have been publish elsewhere. The followings are concise description of the apparatus The output from a synchronously pumped mode-locked dye laser is amplified with the output from a cw Nd YAG regenerative amplifier. The second harmonic (294 nm, 2 kHz, 1-2 mW) of the amplified light (588 nm, 3.2 ps, 2 kHz, 15 mW) was used as a... 

In order to overcome this obstacle, we used a synchronously pumped, mode-locked dye laser, cavity-dumped at 4 MHz and time-correlated single-photon counting detection (18). Because of the higher sensitivity of this experimental system we were able to work at low e, using aqueous rhodamine B solutions with concentrations down to 10" M. To examine the dependence of the fluorescence decays on we chose to work with surface-solution interfaces, so as to minimize the problems associated with inhomogeneous surface coverage, which arise with dry surfaces... 

A three-pulse technique using a synchronously pumped mode-locked dye laser together with a modified Michelson interferometer has been described. By this technique, ps fluorescence decay times may be evaluated without the disadvantages of up-conversion or Kerr cell methods. The suitability of the system for the analysis of low. optical quality samples was suggested. An injection mode-locked Nd-YAG ring laser was used as an excitation source for a zero-background fluorescence study of the time evolution of the emission from large hydrocarbons with 12 ps resolution. ... 

J. Kiihl, H. Klingenberg, D. von der Linde, Picosecond and subpicosecond pulse generation in synchroneously pumped mode-locked CW dye lasers. Appl. Phys. 18,279 (1979)... 

G.W. Fehrenbach, K.J. Gruntz, R.G. Ulbrich, Subpicosecond light pulses from synchronously pumped mode-locked dye lasers with composite gain and absorber medium. Appl. Phys. Lett. 33, 159 (1978)... 

P.K. Benicewicz, J.P. Roberts, A.J. Taylor, Generation of 39 fs pulses and 815 nm with a synchronously pumped mode-locked dye laser. Opt. Lett. 16, 925 (1991)... 

For excitation and detection of fine structure beats with a frequency of 517 GHz subpicosecond light pulses are necessary. For this purpose we used a synchronously pumped mode-locked dye laser with saturable absorber in the dye solution. The dye laser generates light pulses of about ItOO fs duration at a pulse rate of 8U MHz. It is pumped by a frequency doubled actively mode-locked Nd YAG laser and tuned to a wavelength of 589.3 nm for resonant excitation of the Na atoms into the 3p fine structure states. 

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. 

Synchronously Pumped Mode-Locked Dye Laser. Organic dyes have proven to possess excellent properties for the generation of ultrashort laser pulses. Numerous approaches have been taken to the mode-locking of a dye laser, including both active and passive techniques. As a result, tunable continuous wave (cw) dye lasers have been successfully mode-locked over the past 25 years [183, 184], and pulse widths on picosecond and femtosecond timescales have been reported by many groups. 

The experimental arrangement which is similar to that of time-resolved polarization spectroscopy (Fig. 12.11) is depicted in Fig. 12.16. The pulse train is provided by a synchroneously pumped, mode-locked CW dye laser. A fraction of each pulse is split by the beam splitter BS and passes... 

For many applications the time interval AT = 2nd/c between two successive pulses should not be too short. This implies that the cavity length d has to be sufficiently long. In order to avoid inconveniently large geometrical extensions of the arrangement, an optical delay line can be used. Figure 11.9 illustrates a synchronously pumped mode-locked cw dye laser system with such an optical delay line. 

Figure 11.11 shows such a combination of cavity dumping and mode locking. The time interval aT between successive pulses can be controlled between Is and 0.3 ys. The cavity dumping technique can be also applied to synchronously pumped mode-locked cw dye lasers. 

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