Production of large warm plasmas by staged laser heating of solid targets

Abstract

We have shown that it is possible to create a warm plasma (kTi∼50 eV) containing in excess of 1019 electrons using multistage laser heating of a solid target. The target was first irradiated by ∼-10 J Nd/glass laser prepulse, then 600 nsec later by the ∼90 J Nd/glass main pulse. After a delay of ∼4.0 μsec, the mostly un-ionized cloud of target material so created was ionized and heated by irradiation with ≳300 J from a CO2 laser pulse.