Self-assembled nanostructures created by femtosecond laser irradiation are demonstrated in alkali-free aluminoborosilicate glass. The growth of the induced retardance associated with the nanograting formation is three orders of magnitude slower than in silica glass and is observed only within a narrow range of pulse energies. However, the strength of retardance asymptotically approaches the value typically measured in pure silica glass, which is attractive for practical applications. A similar intensity threshold for nanograting formation of about 1 TW/cm² is observed for all glasses studied. The radially polarized vortex beam micro-converter designed as a space-variant quarter-wave retarder for the near-infrared spectral range is imprinted in commercial Schott AF32 glass.

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.

We report ultrafast laser inscription of nanogratings possessing form birefringence in binary sodium germanate glasses in a wide range of ${\mathrm{Na}}_2\mathrm{O}$ content from 3 to 22 mol.%. A minimal number of laser pulses required to induce noticeable form birefringence is shown to grow exponentially with ${\mathrm{Na}}_2\mathrm{O}$ content in glass. Atomic force microscopy showed similarity of their periodical structure and period value to those in the nanogratings formed in fused silica. A sharp pulse duration threshold below which laser pulses do not induce nanogratings in the studied glasses has been revealed. Formation of a nanograting in $22{\mathrm{Na}}_2\mathrm{O}·78{\mathrm{GeO}}_2$ at the studied conditions is accompanied by crystallization of a surrounding submicron layer and partial crystallization inside the nanograting with precipitation of ${\mathrm{Na}}_2{\mathrm{Ge}}_4{\mathrm{O}}_9$ crystals.