Ionization measurements of argon, krypton and xenon atoms with petawatt- to exawatt-per-square-centimeter laser fields.

摘要

Today lasers can generate terawatts (1012 watts) or even petawatts (1015 watts), of optical power that can be focused down to spots as small as a few microns to generate fields on the order of 1011 V/cm. Atoms exposed to such tremendous fields ionize dozens of electrons within a few optical cycles of the laser light. Photoelectrons in this environment can absorb hundreds of thousands of laser photons entering the relativistic regime with speeds greater than v/c≈0.9. Furthermore, the dynamics of relativistic photoelectrons presents a new frontier for light matter interactions due to the inclusion of the laser magnetic field, BLaser. Considerable photoelectron energies and more complicated photoelectron trajectories have a significant impact on scattering processes and radiation mechanisms occurring in the ultrastrong field. To date few experiments have probed the single atom response to such intense fields and the exact nature of the fundamental physics occurring lacks characterization. The goal of this dissertation is to offer some of the first measurements quantifying the response of an isolated atom to an ultrastrong laser field. Ion yields, photoelectron angular distributions and energy spectrums are presented for atoms in laser intensities from 1015-10 19 W cm-2.