Pumping Amplification

Amplification of such short DFDL pulses in excimer laser pumped amplifer cells yields intense pulses with peak powers above 10 y and pulse durations down to 30 fs [11.82]. Optical frequency-doubled dye-laser pulses with a wavelength matched to the gain profile of the excimer laser can also be amplified in excimer-gas discharges [11.79]. 

Schematic diagrams of modem experimental apparatus used for IR pump-probe by Payer and co-workers [50] and for IR-Raman experiments by Dlott and co-workers [39] are shown in figure C3.5.3. Ultrafast mid-IR pulse generation by optical parametric amplification (OPA) [71] will not discussed here. Single-colour IR pump-probe or vibrational echo experiments have been perfonned with OP As or free-electron lasers. Free-electron lasers use...

The energy threshold appears to be dependent on the excitation spot size at constant pump intensity, which indicates that amplification occurs over the whole illuminated area. It should be stated that, despite the large domains, the optical quality within the domains is lower than that of the annealed films. This gives rise to additional scattering losses which decrease the magnitude of the amplification. 

For lock-in amplification the pump is modulated at a reference frequency w (see Fig. 7-1), which means that AT is not constant over time. Rather, its magnitude (and its phase) depends on the modulation frequency [8. In order to find the frequency-dependent A7 (cu), let us assume that the recombination dynamics are monomolecular with a single lifetime r. Then we can write for the number density of excitations N at time / ... 

The layout of the experimental set-up is shown in Figure 8-3. The laser source was a Ti sapphire laser system with chirped pulse amplification, which provided 140 fs pulses at 780 nm and 700 pJ energy at a repetition rate of 1 kHz. The excitation pulses at 390 nm were generated by the second harmonic of the fundamental beam in a 1-nun-thick LiB305 crystal. The pump beam was focused to a spot size of 80 pm and the excitation energy density was between 0.3 and 12 ntJ/crn2 per pulse. Pump-... 

The complex amplitude of the signal field at the output of the crystal is amplified by a factor g with respect to the input field, g is always larger than one so that there is always coherent amplification of the signal field one speaks of parametric amplification. Nonlinear optics provides an amplification different from the amplification occurring in a medium which present population inversion. For a t)q)ical value of the nonlinear coefficient of 1 pm/V, a pump of... 

In the past few years, erbium doped materials gained much attention in the field of optical communications, since the Er ion shows a broad optical emission at 1540 nm [111], within the main wavelengths window in the telecommunication technology. For this reason Er can be suitable as an active element for the generation and amplification of light in optical devices [112,113], also if limitations for the realization of an efficient planar amplifier are related to the small cross section for Er excitation (typically 10 -10 cm according to the matrix). In order to enhance Er ion pumping efficiency, a possible... 

Chemical heat pump uses chemical reaction for thermal energy storage and conversion. The heat pump operation is based on reaction equilibrium relationship, and has two operation modes. Figure 221 shows equilibrium relationship of chemical heat pump cycle for Mg0/H20 system at (a) heat amplification and cooling mode and (b) heat transformation mode [26], Figure 222 shows... 

Figure 221. Equilibrium relationship of chemical heat pump cycle for MgO/EFO system (a) heat amplification and cooling mode, (b) heat transformation mode...

Figure 222. Mg0/H20 chemical heat pump operation in heat amplification mode with cooling operation...

Note In centrifugal pumps, the typical damped response to unbalance does not show a peak in displacement at resonance large enough to assess the amplification factor. With this limitation, assessment of the damped response to unbalance is restricted to comparing rotor displacement to the available clearance. 

The high-speed pumps or compressors must operate in a region away from any critical speed. The amplification factor used to indicate the severity of the critical speed is given by the relationship... 

Fig. 11 Excited state absorption spectra of 3 (1) and 11 (2) in ACN, 17 (3) in THF and Rhodamine 6G (4) in ethanol. Normalized fluorescence of 3, 11 in ACN, and 17 in THE. Fluorescence spectrum of Rhodamine 6G in ethanol is normalized to its maximiun of amplification (curve 4). Pump energy p 350 xj at excitation wavelength Xp = 355 nm...

The Priore effort in France demonstrated an amplification of this exact action in cells, in thousands of successful lab animal tests in the 1960s and early 1970s, but no one could understand the mechanism. At the time, phase conjugate optics as we know it today had not been developed—much less its extension into NLO pumping in the time dimension. Nonetheless, revolutionary cures of terminal tumors, infectious trypanosomiasis, and atherosclerosis were rigorously demonstrated by the scientists working with the Priore method. 

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