Super-Resolution Recording by an Organic Photochromic Mask Layer

By using the super-resolution near-field structure (super-RENS) method, the super-resolution recording marks are obtained practically by an organic photochromic diarylethene mask layer, under much lower recording laser power of 0.45 mW. The size of recording marks is decreased by 60% (from 1.6 μm to 0.7 μm) for a diarylethene (photo-mode) recording layer by the optical detection method (limited by optical diffraction), or decreased by 97% (from 1600 nm to 50 nm) for a heptaoxyl copper phthalocyanine (thermo-optical) recording layer, the latter is much smaller than the limitation of optical diffraction. In order to obtain a desirable result, a proper extent of photochemistry reaction in the mask layer is needed. Thus, the super-resolution recording marks can be obtained by adjusting the concentration of diarylethene in the mask layer, the recording laser power, and the moving speed of the sample disc.