Figure 5
Spectral distribution of the relevant optical quantities of the materials involved.
(a) Dielectric function of the niobium (measured using 300 nm thick film, solid (dashed) line: real (imaginary) part of εNb). (b) Material dispersion of the three used dielectric materials (green: niobium oxide, purple: aluminum oxide, brown: fused silica). Since all three dielectrics have very low absorption in the spectral interval relevant here, the absorption coefficient has not been plotted.
