This contribution reports, for what we believe is the first time, on V O 2 -based thin-film coatings on flexible Al substrates exhibiting a tunable positive emittance-switching Δ ε = ( ε H - ε L ) > 0 . More precisely, a layered stack of a- S i : H / S i O 2 / V O 2 on flexible Al sheets presents minimum and maximum values of emissivity of about 0.18 and 0.57 at 40ºC and 83ºC, respectively, and hence allows an emittance-switching Δ ε of 0.39 and a relative variation Δ ε / ε Λ of ∼ 217 % . Such variations fit with the potential applications of such coatings as smart radiation devices in small satellites and spacecraft.

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In line with the renewed interest in developing novel Non Linear Optical (NLO) materials, natural Lycopene’s NLO Properties are reported for the first time within the scientific literature. Correlated to its 1-D conjugated π-electrons linear conformation, it is shown that natural Lycopene exhibits a significantly elevated 3rd order nonlinearity χ(3) as high as 2.65 10−6 esu, the largest value of any investigated natural phyto-compound so far, including β-carotene. In addition to a saturable absorption, the corresponding observed self-defocusing effect in Lycopene seems to be the result of a thermal nonlinearity. The nonlinear response coupled to the observed fluorescence in the Visible spectral range points to a potential photodynamic therapy application as well as the possibility of engineering of novel hybrid Lycopene based NLO nano-materials.