<title>Efficient high-temperature plasma production by the irradiation of a short-pulse laser on a very thin membrane</title>

Abstract

For realizing a table-top x-ray laser or a compact short wavelength x-ray laser, improvement of the pumping efficiency is one of the most important points. Thermal conduction into inside of the target should suppress rising up of electron temperature of a laser-produced plasma. Then, the plasma produced on a very thin membrane target gets rid of this energy loss, and the efficiency of the high temperature plasma production will be increased. Moreover, density of the plasma from a membrane decreases very rapidly because of the small amount of target limited by the membrane thickness. These features of membrane plasma are suitable in recombination x- ray laser. To confirm the advantages of this pumping scheme, we produced the plasma on a thin membrane and the heating and expansion was evaluated. Experimentally observed spectral lines of H-like and He-like Si ions show effective heating and ionization of the plasma for a membrane target. Electron density evaluations and plasma expansion velocity measurements confirm rapid plasma expansion from the membrane target. Theoretical hydrodynamic simulation also showed the effective heating and ionization of the plasma from the membrane target.© (1997) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.