Abstract
GOLD (Grupo de Óptica de Láminas Delgadas) is devoted to the development of novel coatings with challenging performance in the far and the extreme ultraviolet (FUV-EUV, 50–200 nm). One of the main goals of this research is to provide the communities of astronomy, solar physics and atmospheric physics with coatings with high reflectance or transmittance at a target wavelength or band, and high rejection of the out-of-band at this complicated spectral range. Above the transparency cutoff of MgF2 (115 nm), transmittance filters based on Al/MgF2 multilayers have been developed peaked at wavelengths as short as 124 nm, with a peak transmittance of 27% and a FWHM of 12 nm for a non-aged coating. Below 115 nm, a research on reflectance filters has recently started with very promising results on filters peaked at the 83.4 nm OII spectral line. Fresh filters with 27% peak reflectance at normal incidence and a FWHM of 14 nm have been obtained. Furthermore, the peak reflectance wavelength of these filters can be tuned by rotation. A filter peaked at 83 nm at normal incidence will shift to ∼73 nm at 30 deg from the normal and to ∼58 nm at 45 deg. These novel reflective filters based on Al, Yb and SiO must still demonstrate stability over time.
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Aznárez, J.A., Larruquert, J.I., Méndez, J.A.: Far ultraviolet absolute reflectometer for optical constants determination of ultra high vacuum prepared thin films. Rev. Sci. Instrum. 67, 497–502 (1996)
Méndez, J.A., Larruquert, J.I., Aznárez, J.A.: Preservation of far-UV aluminum reflectance by means of overcoating with C 60 films. Appl. Opt. 39, 149–156 (2000)
Larruquert, J.I., Keski-Kuha, R.A.M.: Reflectance measurements and optical constants in the extreme ultraviolet for thin films of ion-beam-deposited SiC, Mo, Mg2Si, and InSb and of evaporated Cr. Appl. Opt. 39, 2772 (2000)
Keski-Kuha, R.A.M., Osantowski, J.F., Herzig, H., Gum, J.S., Toft, A.R.: Normal incidence reflectance of ion beam deposited SiC films in the EUV. Appl. Opt. 27, 2815 (1988)
Osantowski, J.F., Keski-Kuha, R.A.M., Herzig, H., Toft, A.R., Gum, J.S., Fleetwood, C.M.: Optical coating technology for the EUV. Adv. Space Res. 11(11), 185 (1991)
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Fernández-Perea, M., Vidal-Dasilva, M., Larruquert, J.I. et al. Novel narrow filters for imaging in the 50–150 nm VUV range. Astrophys Space Sci 320, 243–246 (2009). https://doi.org/10.1007/s10509-008-9798-3
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DOI: https://doi.org/10.1007/s10509-008-9798-3