Bound-Electron Nonlinearity Beyond the Ionization Threshold.

ABSTRACT: We present absolute space- and time-resolved measurements of the ultrafast laser-driven nonlinear polarizability in argon, krypton, xenon, nitrogen, and oxygen up to ionization fractions of a few percent. These measurements enable determination of the strongly nonperturbative bound-electron nonlinear polarizability well beyond the ionization threshold, where it is found to remain approximately quadratic in the laser field, a result normally expected at much lower intensities where perturbation theory applies.

SUBMITTER: Wahlstrand JK 

PROVIDER: S-EPMC6074032 | biostudies-literature | 2018 May

REPOSITORIES: biostudies-literature