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arXiv · 2208.14223

Characterization of plasmas driven by laser wavelengths in the 1.064-10.6 $\mu$m range as future extreme ultraviolet light sources

D. J. Hemminga·O. O. Versolato·J. Sheil
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Abstract

We characterize the properties of extreme ultraviolet (EUV) light source plasmas driven by laser wavelengths in the $\lambda_{\mathrm{laser}} = 1.064 - 10.6 $ $\mu$m range. Detailed numerical simulations of laser-irradiated spherical tin microdroplet targets reveal a strong laser-wavelength dependence on laser light absorptivity and the conversion efficiency of generating EUV radiation. Radiative losses are found to dominate the power balance for all laser wavelengths, and a clear shift from kinetic to in-band radiative losses with increasing laser wavelength is identified. We find that the existence of maximum conversion efficiency, near $ \lambda_{\mathrm{laser}} = 4 $ $\mu$m, originates from the interplay between the optical depths of the laser light and the in-band EUV photons for this specific target geometry.

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D. J. Hemminga, O. O. Versolato, J. Sheil. 2022-08-28. Characterization of plasmas driven by laser wavelengths in the 1.064-10.6 $\mu$m range as future extreme ultraviolet light sources. https://doi.org/10.1063/5.0125936

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