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
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 10-4 as in the transparent state. This is of great promise to applications requiring large optical contrast (e.g., optical switches).
1 avon Rottkay, Klaus1 aRubin, Michael, D.1 aDuine, Peter, A. uhttps://facades.lbl.gov/publications/refractive-index-changes-pd-coated01659nas a2200193 4500008004100000050001500041245009400056210006900150260002500219520098200244100002301226700002301249700002101272700002501293700002701318700002401345700002101369856007501390 1998 eng d aLBNL-4227700aEffect of Hydrogen Insertion on the Optical Properties of PD-Coated Magnesium Lanthanides0 aEffect of Hydrogen Insertion on the Optical Properties of PDCoat aLondon, U.K.c9/19983 aMetallic magnesium lanthanide thin films upon insertion of hydrogen transform to a highly transparent hydride phase. With a Pd overlayer, the transformation can be produced either by electrochemical insertion of hydrogen or by exposing the film to hydrogen gas. Unlike amorphous oxide electrochromics, the transformation is accompanied by a large change in visible reflectance (about 50%). The optical switching effect in these materials is investigated in terms of changes in the complex refractive index as determined by variable-angle spectroscopic ellipsometric and normal-incidence radiometric measurements over the solar spectrum. Furthermore the optical effect of converting the Pd caplayer to Pd-H was determined. It is shown that the pd layer limits the visible transmittance of the hyrdrided stack to about 35-40%. Whereas the extinction coefficient of the dehydrided LnMg-layers at 550 nm is between 2.2 and 3.1, it is as low as 10-4 in the transparent state.
1 avon Rottkay, Klaus1 aRubin, Michael, D.1 aMichalak, Franck1 aArmitage, Robert, D.1 aRichardson, Thomas, J.1 aSlack, Jonathan, L.1 aDuine, Peter, A. uhttps://facades.lbl.gov/publications/effect-hydrogen-insertion-optical