Thermal-induced optical properties of a PdOx mask layer in an optical data storage system with a superresolution near-field structure.

Optical-thermal and thermal-optical properties of a PdOx mask layer in a system with a superresolution near-field structure are investigated with a Z-scan technique and a heating experiment. The high photothermal stability of the PdOx mask is shown, and the reversible limit of the PdOx mask layer and a weak switch effect are revealed. The PdOx decomposition, which results in a bubble with Pd particles, is confirmed, and the laser-induced physical and chemical mechanisms in the PdOx mask layer are clarified and discussed. Our microscopic studies and heating analysis are consistent with the Z-scan results. The PdOx mask sample is also compared briefly with a PtO2 mask layer that has the same structure.