HIGH-ENERGY ION EXPLOSION OF ATOMIC CLUSTERS - TRANSITION FROM MOLECULAR TO PLASMA BEHAVIOR

We have studied the high-intensity femtosecond photoionization of iner tially confined noble-gas clusters. The explosion of the resulting hig hly ionized, high-temperature microplasma. ejects ions with substantia l kinetic energy. Wr have observed Xe ions with kinetic energy up to 1 MeV and charge states as high as 40(+). This ion energy is over three orders of magnitude higher than has previously bern observed in the C oulomb explosion of molecules or clusters of any kind and indicates th at there is a fundamental shift in the nature of intense laser-matter interactions between molecules and large clusters.