Multidimensional data recording inside nanoporous high-silica glass by a femtosecond laser beam has been investigated. It is shown that three femtosecond laser pulses at pulse repetition rates up to 1 MHz are sufficient for recording 3 bits of information inside nanoporous glass, which is an order of magnitude lower than the number of pulses required for data writing in silica glass and provides a corresponding gain in the data writing speed. Multilayer data recording and reading were demonstrated providing the storage density corresponding to the capacity of 25 GB in the optical compact disc form factor. An outstanding thermal stability of the proposed optical data storage is confirmed by the 24 h long heat treatment at 700°C, which could not damage the recorded data.

Gold nanoparticles precipitated in transparent glass-ceramics could pave the way for the development of multifunctional materials that are in demand in modern photonics and optics. In this work, we explored the effect of gold nanoparticles on the crystallization, microstructure, and optical properties of ZnO-MgO-Al₂O₃-SiO₂ glass containing TiO₂ and ZrO₂ as nucleating agents. X-ray diffraction, transmission electron microscopy, Raman, and optical spectroscopy were used for the study. We showed that gold nanoparticles have no effect on the formation of gahnite nanocrystals during the glass heat treatments, while optical properties of the glass-ceramics are strongly dependent on the gold addition. A computational model was developed to predict optical properties of glass during the crystallization, and the possibility for adjusting the localized surface plasmon resonance band position with the heat treatment temperature was shown.