Optical recording properties of metal-azo dye thin film with super-resolution near-field structure

A novel metallized azo dye has been synthesized and its thin film on K9 glass has been prepared. The absorption spectra, thermal character and static optical recording properties with Bi mask layer super-resolution near-field structure (Super-RENS) of the dye were investigated. The results show that the dye film has a broad absorbance band in the region of 450-650nm and the maximum absorbance wavelength is located at 603nm, which is red shifted 17nm comparing with that of its chloroform solution, a steep absorbance falling edge in 603-650 is observed. It is found that the new metallized azo dye occupies excellent thermal stability, initiatory decomposition temperature is at 270°C and the mass loss is about 48% in a narrow temperature region (15°C). Static optical recording tests with and without Super-RENS were carried out using a 650nm semiconductor diode laser with recording power of 7mW and laser pulse duration of 200ns. The AFM images show that the diameter of recording mark on the dye film with Bi mask layer is reduced about 42% comparing with that of recording mark on the dye film without super-resolution near-field structure. It is indicate that Bi can well performed as a mask layer of dye recording layer and the metallized azo dye can be a promising candidate for recording medium with super-resolution near-field structure.