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The requirements for the production of high power, subplcosecond laser pulses are reviewed. Use of the chirped-pulse amplification technique makes solid-state materials competitive with dyes and excimers for the production of subplcosecond pulses. In cases where both high power and short pulses are required, solid-state materials are shown to be the material of choice. As an example, the design and performance of a 3.2 Terawatt Nd:Glass laser system based on chirped-pulse amplification is presented.© (1990) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

An ultrafast soft x-ray streak camera has been coupled to a Wolter axisymmetric x-ray microscope. This system was used to observe the dynamics of laser fusion targets both in self emission and backlit by laser produced x-ray sources. Spatial resolution was 7 pm and temporal resolution was 20 ps. Data is presented showing the ablative acceleration of foils to velocities near 107 cm/sec and the collision of an accelerated foil with a second foil, observed using 3 keV streaked x-ray backlighting. Good agreement was found between hydrocode simulations, simple models of the ablative acceleration and the observed velocities of the carbon foils.© (1983) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

In this paper we describe the operation and applications of a commercially available framing camera capable of four separate two-dimensional images with each frame having a 120-ps gate width. The time separation between frames can be selected arbitrarily. Fast gating of a single frame is accomplished by using a wafer image intensifier tube in which the cathode is capacitively coupled to an external electrode placed outside of the input window of the tube. This electrode is then pulsed relative to the microchannel plate by a narrow (120 ps), high-voltage pulse. The transmission of the tube as a function of time has been verified using a laser-diode pulser and is approximately Gaussian with a FWHM of 120 ps. Multiple frames are obtained by using multiple gated tubes which can then share a single bias supply and pulser with relative gate times selected by the cable lengths between the tubes and the pulser. A beamsplitter system has been constructed which produces a separate image for each tube from a single scene. In the present system, the tubes use S-20 photocathodes with an 18 mm diameter and quartz input windows. Spatial resolution is unchanged between d.c. and fast gated operations and has been measured to 10 1p/mm. Applications to time-dependent behavior will be presented.

New short -pulse laser technology has made possible the production of extremely bright ( >1018 W /cm2 -sr)laser sources. The use of these new techniques on large scale Nd:glass based laser systems would make it possible to produce 1000 TW (Petawatt) pulses. Such pulses would yield focused intensities exceeding 1021 W /cm2corresponding to an electric field in excess of 100 e /a02 and an energy density equivalent to that of a 10 keVblackbody. The first step towards the realization of such a source is the development of a compact 10 TW laser. The design of a 10 TW table -top laser and some potential applications are described.Introduction A new short -pulse laser technology known as chirped -pulse amplification (CPA)1,2 has made possible the production of extremely bright ( >1018 W /cm2 -sr) laser sources. The use of these new techniques on large scale Nd:glass based laser systems would push the available laser intensity over three orders of magnitude beyondthe current state of the art. Peak powers in excess of 1000 TW ( =1 Petawatt) can be achieved corresponding to

Significant progress toward the goal of producing high Power, high coherence x-ray lasers has been made. Lasing at wavelengths as low as 66 A has been achieved in a nickel like laser scheme which is scalable to sub-44 A wavelengths. In addition, x-ray laser cavities, x-ray holography, and an applications beamline have been demonstrated.

Since the successful demonstration of gain in neon-like selenium using an exploding foil amplifier, the x-ray laser group at Lawrence Livermore National Laboratory has investigated further the exploding foil amplifier concept for use in XUV lasers. Results are reported of the characteristics of selenium amplifiers up to 50 mm in length. Observation of at least 16 gain lengths for the 206 A line of selenium is reported. Output powers in excess of 1 MW have been measured in pulses of approximately 200 picoseconds. The effects of refraction on the performance of long amplifiers have been studied. The occurrence time of the x-ray laser output relative to the input heating pulse has been measured and found to be in disagreement with a recent model that suggests three-body recombination driven by rapid radiative cooling as the inversion process in the selenium plasma.

X-ray holography offers the potential for obtaining high resolution three-dimensional images of in vitro biological microstructures. Significant progress toward this goal has been achieved with holography systems using synchrotron x-ray sources and recently spatial resolutions as small as 40 nm have been demonstrated. These experiments required x-ray exposures of an hour or longer, which makes high spatial resolution difficult to achieve in live biological specimens because of blurring of the image. This blurring is caused by specimen motion and will prohibit the imaging of dynamical processes within the specimen. A possible solution to this problem is to exploit the extremely high brightness and long coherence lengths produced by x-ray lasers and create the hologram with exposure times of less than 1 nsec. This report presents the results from an experiment in which an x-ray laser was used to produce x-ray holograms. The holography geometry used was a Gabor in-line type modified by the inclusion of a high reflectivity multi-layer x-ray mirror used as a narrow bandpass filter. The x-ray mirror had a flatness and roughness of less than X/100 (where X is the wavelength) at the x-ray laser wavelengths.

Ultrashort (