Abstract

Recently, several authors have proposed that x-ray lasers pumped by electron-ion recombination are feasible if cold electrons can be produced from the interaction of a high-intensity laser pulse with a gas sample [1]. Burnett and Corkum [2] have used a model based on tunneling ionization to predict that cold electrons can be produced from such an interaction. Initial experimental tests of such a prediction yielded conflicting results [2,3]. Measurements [4] have not previously been performed simultaneously at high density (where additional heating mechanisms can operate [5]) and on sub-picosecond time-scales relevant to transient recombination lasers [1].

© 1994 Optical Society of America