Functionalized switchable mirrors

The evolution of electrical resistivity (p) and optical transmittance (Topt) for red light as a function of hydrogen exposure time for a representative switchable mirror are shown in fig. 1. As the hydrogen concentration increases, there is an initial weak rise in p due to impurity scattering, and there after it decreases steadily until it reaches a minimum in the dihydride phase. At this point, YH2 has a resistivity that is 5 times lower than that of pure Y. At higher H concentrations, p increases by several orders of magnitude and is only limited by the conductivity of the Pd over layer. The optical transmittance remains low until in the dihydride... 

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