Optimization of the focused flux of high harmonics
Following the theoretical predictions , the observation of two-photon processes by interaction of vacuum ultraviolet (VUV) radiation with inner-shell levels of atoms requires focused intensities in the 1013-1014 W/cm2 range. Our aim is to reach this regime in order to study non-linear optics at these wavelengths. We first optimized the high harmonic conversion efficiency in argon by studying the best experimental conditions for phase-matching, concentrating on focus geometry related to laser energy, cell length and position relative to the focus. We then studied the resulting harmonic beam focusability by a toroidal mirror (f=10 cm) and made an image of the harmonic focus. We conclude with an evaluation of the focused intensity that we are able to reach experimentally.
KeywordsRadiation Argon Theoretical Prediction Conversion Efficiency Laser Energy
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- 3.Y. Kobayashi , Opt. Lett. 23, 64 (1998)Google Scholar
- 6.S. Kazamias , Phys. Rev. Lett. (to be published)Google Scholar
- 8.A. L’Huillier , Phys. Rev. A 48, R3433 (1993)Google Scholar
- 10.R.A. Bartels , Science 297, 376 (2002)Google Scholar
- 15.L. Le Déroff , Opt. Lett. 23, 1544 (1998)Google Scholar
- 16.M. Schnuerer , Appl. Phys. B 70, S227 (2000)Google Scholar
- 17.C. Valentin , Opt. Lett. (to be published)Google Scholar