Optical switching property of Pd-capped Mg–Ni alloy thin films prepared by magnetron sputtering

Pd-capped Mg–Ni alloy thin films were prepared by magnetron sputtering, on glass substrates, and the dependence of the optical switching property of these films on alloy composition and temperature has been investigated using diluted hydrogen gas and dry air for changing. The transition from the transparent state to the mirror state by dehydrization shows strong dependence on both factors, while the hydrization transition has weak dependence. At higher temperature, the dehydrization is much faster for Mg-rich Mg–Ni thin film whose transition is very slow at room temperature. By using heated air to change from the transparent state to the mirror state, a fast switching can be done for Mg-rich Mg–Ni alloy thin film which has a wide optical modulation range.