X rays from microstructured targets heated by femtosecond lasers

Opt Lett. 1994 Apr 1;19(7):484-6. doi: 10.1364/ol.19.000484.


We have demonstrated efficient conversion of ultrashort-pulse laser energy to x rays with energies above 1 keV, using laser-produced plasmas generated on a variety of microstructured surfaces. Lithographically produced grating targets generated 0.1 mJ of kilo-electron-volt x rays, and porous gold and aluminum targets emitted 1 mJ. This represents an improvement of a factor of 100 over flat targets. The K-shell emission spectrum of porous aluminum was composed primarily of heliumlike spectral lines.