01366nas a2200169   4500008004100000022001500041245010600056210006900162260001200231300001200243490000700255520079100262100002301053700002301076700002101099856007601120       1999                        eng d  a0021-8979 00aRefractive Index Changes of Pd-Coated Magnesium Ianthanide Switchable Mirrors Upon Hydrogen Insertion0 aRefractive Index Changes of PdCoated Magnesium Ianthanide Switch  c01/1999  a408-4130 v853 a<p>The optical effect upon insertion of hydrogen into Pd-coated magnesium lanthanide switchable mirrors is investigated in terms of the changes of their complex refractive indices. A significant change in the optical constants of LnMg layers is seen between the as-deposited state and the dehydrided state after one cycle. Furthermore, the optical effect of switching the Pd cap layer to a PdH cap layer was determined. It is shown that the Pd layer mainly limits the visible transmittance of the hydrided stack to about 35%-40%. Whereas the extinction coefficient of dehydrided LnMg layers at 550 nm is between 2.2 and 3.1, it is as low 10<sup>-4</sup> as in the transparent state. This is of great promise to applications requiring large optical contrast (e.g., optical switches).</p>1 avon Rottkay, Klaus1 aRubin, Michael, D.1 aDuine, Peter, A.  uhttps://facades.lbl.gov/publications/refractive-index-changes-pd-coated