Generation of VUV, EUV, and X-ray light using VUV-UV-VIS lasers

摘要

A method for extending and enhancing bright coherent high-order harmonic generation into the VUV-EUV-X-ray regions of the spectrum involves a way of accomplishing phase matching or effective phase matching of extreme upconversion of laser light at high conversion efficiency, approaching 10−3 in some spectral regions, and at significantly higher photon energies in a waveguide geometry, in a self-guiding geometry, a gas cell, or a loosely focusing geometry, containing nonlinear medium. The extension and enhancement of the coherent VUV, EUV, X-ray emission to high photon energies relies on using VUV-UV-VIS lasers of shorter wavelength. This leads to enhancement of macroscopic phase matching parameters due to stronger contribution of linear and nonlinear dispersion of both atoms and ions, combined with a strong microscopic single-atom yield.

主权项

1. The method of generating coherent emission within the VUV, EUV, and X-ray region of the spectrum comprising the steps of:
(a) providing a nonlinear medium comprising a gas for high harmonic generation (HHG) of laser light; (b) selecting the pressure of the nonlinear medium; (c) generating a laser driving pulse having a selected wavelength within the VUV-UV-VIS region of the spectrum and a selected peak intensity above 5×1014 W/cm2; and (d) focusing the driving pulse into the nonlinear medium to cause HHG upconversion resulting in a generated pulse within a selected range within the VUV, EUV, and X-ray region of the spectrum;wherein steps (a)-(d) effectively phase match the driving pulse and the generated pulse sufficiently to result in a coherent generated pulse wherein the coherence length is comparable to the absorption depth.