Sandia National Laboratories

navigation panel

The next step in development for the Z-Beamlet is to modify the laser to increase its peak power a thousand-fold from terawatts to petawatts. Petawatt experiments may begin as early as 2004, and design of new components and conversion of the laser are progressing. Z-Beamlet will continue to support its stockpile support mission as new capabilities are added.

Petawatt Image

Innovative experiments on the frontier of our current understanding of physics require power levels that would destroy the laser itself. A way to increase the power of the laser pulse without damaging laser components is to stretch the pulse out in time as it passes through the laser and is amplified. Then, just before it strikes the target, it is compressed into an extremely short, high-energy pulse. This process, called Chirped Pulse Amplification (CPA), requires extensive modification of Z-Beamlet and a means of compressing the pulse, which is advancing the state of the art in its design.

With the petawatt capability, Z-Beamlet experiments will be conducted in the following areas:

Fast Ignitor Fusion Research. Although lasers can be used to compress a target, at Sandia this function is performed by the Z-Accelerator. However, the perfectly uniform compression of the target that is required in fusion experiments is difficult to attain. Instead, a short, well-timed pulse from Z-Beamlet will act as a spark plug to initiate a fusion burn in a less than perfectly compressed target, reducing the required uniformity to achievable levels. This short cut in fusion experiments may ultimately make it possible to produce more energy from experiments than is put into them, yielding valuable insights into fusion processes.

Radiography. The petawatt capability will provide X-rays up to the MeV range (instead of the <10 keV range currently available). More penetrating X-rays will permit images to be made of denser materials undergoing much more fleeting transformations that could contribute valuable knowledge to the study of weapons effects and fusion processes. Protons generated from the petawatt laser driven backlighting of targets could be used to create a new kind of image of materials, structures, and events.

Pure Physics. The extremely high power levels to which target materials will be exposed may produce reactions that are unexpected and generate responses that are of great interest to scientists. While the exact nature of the discoveries that might be produced is impossible to predict, the transmutation of materials and the production of exotic atomic particles might be studied.