Influence of the intensity gradient upon HHG from free electrons scattered by an intense laser beam

Ankang Li, Jiaxiang Wang, Na Ren, Pingxiao Wang, Wenjun Zhu, Xiaoya Li, Ross Hoehn, Sabre Kais

Research output: Contribution to journalArticle


When an electron is scattered by a tightly focused laser beam in vacuum, the intensity gradient is a critical factor to influence the electron dynamics. In this paper, we have further investigated its influence upon the electron high-harmonic generation (HHG) by treating the spacial gradient of the laser intensity as a ponderomotive potential. Based upon perturbative quantum electrodynamics calculations, it has been found that the main effect of the intensity gradient is the broadening of the originally line HHG spectra. A one-to-one relationship can be built between the beam width and the corresponding line width. Hence, this finding may provide us a promising way to measure the beam width of intense lasers in experiments. In addition, for a laser pulse, we have also studied the different influences from transverse and longitudinal intensity gradients upon HHG.

Original languageEnglish
Pages (from-to)95-101
Number of pages7
JournalApplied Physics B: Lasers and Optics
Issue number1
Publication statusPublished - 2014


ASJC Scopus subject areas

  • Physics and Astronomy(all)
  • Physics and Astronomy (miscellaneous)

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