Phase transformation under direct laser writing in a YAG single crystal

The transformation from Y3Al5O12 to perovskite YAlO3 crystal phase was observed during ultrafast laser writing in the bulk of a Y3Al5O12 single crystal. The control of the phase transformation was demonstrated by tuning parameters of laser writing. The phenomenon is interpreted in terms of structural changes in the overheated garnet melt under laser heating followed by rapid solidification, and at least 1-ms dwell time of overheated melt is required to start spontaneous crystallization. The appearance of the perovskite phase was confirmed by Raman spectroscopy, quantitative phase and polarization microscopies

Functional birefringent elements imprinted by femtosecond laser nanostructuring of multi-component glass

A decade ago, a new type of self-organization process was observed in the bulk of SiO2 glass after irradiation with ultrashort laser pulses [1]. Under certain irradiation conditions, highly ordered nanostructures with features smaller than 20 nm could be formed in the irradiated volume. The sub-wavelength arrangement of these structures results in form birefringence, which was recently exploited for demonstrating a variety of functional optical elements in silica glass [2]. Despite excellent physical and chemical properties of fused silica, the applications of this glass are limited due to the expensive manufacturing process associated with high melting temperature. Recently the evidence of laser-induced nanogratings in glasses other than SiO2 was reported, including GeO2 glass [3], binary titanium silicate glass (ULE, Corning) and multicomponent borosilicate glass (Borofloat 33, Schott) [4]. However, birefringence induced in borosilicate glass was more than one order of magnitude lower than in pure SiO2 glass

Direct writing of birefringent elements by ultrafast laser nanostructuring in multicomponent glass

Self-assembled nanostructures created by femtosecond laserirradiation 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 silicaglass and is observed only within a narrow range of pulse energies. However, the strength of retardance asymptotically approaches the value typically measured in pure silicaglass, 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

Dataset for Direct writing of birefringent elements by ultrafast laser nanostructuring in multicomponent glass

Self-assembled nanostructures created by femtosecond laserirradiation 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 silicaglass and is observed only within a narrow range of pulse energies. However, the strength of retardance asymptotically approaches the value typically measured in pure silicaglass, 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.</span

Advances in femtosecond laser nanostructuring in glass: from printed geometrical phase optics to eternal data storage

Formation of sub-wavelength periodic structures in bulk transparent materials during irradiation with intense ultrashort light pulses remains a mystery. Nevertheless the phenomenon has enabled unique applications ranging from printed flat optics to eternal data storage