Abstract:

When an intense laser beam is focused onto a plasma, it can excite a plasma wave that propagates with a phase velocity close to the speed of light and has associated with it an electric field on the order of 10's to 100's of GV/m. This is 3 to 4 orders of magnitude larger than for conventional accelerators and hence offers the possibility of developing compact high energy accelerators. Currently we are working on the development of a "table-top" 1 GeV laser driven accelerator which consists of three parts: (i) an all-optical injector using laser triggering of electrons in a plasma structure, (ii) a plasma based "optical fiber" for guiding of high intensity laser beams over macroscopic distances (1-10 cm scale length) and (iii) beam diagnostics with femtosecond resolution. The research is carried out using the l'OASIS multi-terawatt laser facility. Applications of laser driven accelerators are also pursued such as generation of coherent far-infrared and THz radiation, production of femtosecond x-ray pulses by laser accelerated electron bunches, and radio-isotope production of positron emitters.