High-order harmonic generation from ions in a capillary discharge
Date
2006
Authors
Rocca, Jorge J., author
Kapteyn, Henry C., author
Murnane, Margaret M., author
Walker, Barry C., author
Cohen, Oren, author
Berrill, Mark, author
Grisham, Michael, author
Popmintchev, Tenio, author
Reagan, Brendan, author
Gaudiosi, Dsvid M., author
Journal Title
Journal ISSN
Volume Title
Abstract
We demonstrate a significant extension of the high-order harmonic cutoff by using a fully-ionized capillary discharge plasma as the generation medium. The preionized plasma dramatically reduces ionization-induced defocusing and energy loss of the driving laser due to ionization. This allows for significantly higher photon energies, up to 150 eV, to be generated from xenon ions, compared with the70 eV observed previously. We also demonstrate enhancement of the harmonic flux of nearly 2 orders of magnitude at photon energies around 90 eV when the capillary discharge is used to ionize xenon, compared with harmonic generation in a hollow waveguide. The use of a plasma as a medium for high-order harmonic generation shows great promise for extending efficient harmonic generation to much shorter wavelengths using ions.