Efficient Pulse Compression Research Articles

High Efficiency Pulse Compression by Raman Induced Cavity Dumping

Raman induced cavity dumping has been demonstrated theoretically and experimentally as an efficient technique of pulse compression. Through intracavity stimulated Raman scattering the electromagnetic energy at a primary frequency is down-converted and extracted from a storage cavity containing the Raman medium. Several experimental set-ups have been tested, concerning oscillators and amplifiers, using different pumping techniques. Results differ slightly according to the technique used, but pulse shortenings exceeding 10 and quantum efficiencies larger than 80 per cent were obtained. This method developed in the case of a ruby laser could also be used with large power lasers of any wavelength from the ultraviolet to the far infrared.

Pulse compression by Raman induced cavity dumping of a homogeneously pumped oscillator and amplifier

High efficiency pulse compression has been obtained by using a homogeneously pumped intracavity Raman oscillator or amplifier. Using a 25 ns duration ruby laser as the pump source and compressed hydrogen as the Raman scatterer, this technique, like a previous externally pumped intracavity Raman oscillator, has produced 2 ns duration second Stokes pulses with near 50% quantum efficiency. With the present technique the spatial quality of the second Stokes beam has been very good because of an off-axis pumping of the cavity. Working as an amplifier, the system has reproduced perfectly both temporal shape and divergence of a nearly diffraction limited input second Stokes beam.

Subpicosecond pulse generation in a branched passively mode-locked Nd-glass laser

A two-branch passively mode-locked Nd-glass laser is applied to generate light pulses down to 0.4 ps duration (average duration 0.9 ps). The laser action is initiated in a path of high saturable dye transmission and then switched to a branch of low saturable dye transmission for efficient pulse compression. The experimental results are compared with computer simulations.

Plasma KrF laser pulse compressor

The use of a plasma medium for the compression of KrF laser light to pulse widths suitable for laser-driven fusion applications is described. The results indicate that efficient pulse compression can be realized. A particular feature is the absence of the troublesome backward second-Stokes wave found in gas cell compressors.

A DC Triggered High-Speed High-Power Microwave Spark Gap Switch

Operation of a microwave spark gap switch triggered with a short high-voltage pulse is described. C-band power of 1 MW peak and 4/spl mu/s pulse width was switched in less than 10 ns at 100 pps with less than 0.3 dB arc loss in air at atmospheric pressure. Use in a cavity resonator to give an efficient pulse compression circuit is described. Switch recovery and turn off data are given.