The Effect of Combining Femtosecond Laser and Electron Irradiation on Silica Glass.

This study investigates the structural and optical responses of silica glass to femtosecond (fs) laser irradiation followed by high-energy electron (2.5 MeV, 4.9 GGy) irradiation.

Nano-FTIR spectroscopy reveals SiO densification within fs-laser induced nanogratings.

This study explores the structural transformations induced by femtosecond (fs) laser inscriptions in glass, with a focus on type II modifications (so-called nanogratings), crucial for advanced optical and photonic technologies. Our novel approach employs scattering-type scanning near-field optical microscopy (s-SNOM) and synchrotron radiation nanoscale Fourier-transform infrared spectroscopy (nano-FTIR) to directly assess the nanoscale structural changes in the laser tracks, potentially offering a comprehensive understanding of the underlying densification mechanisms. The results reveal the first direct nanoscale evidence of densification driven by HP-HT within fs-laser inscribed tracks, characterized by a significant shift of the main infrared (IR) vibrational structural band of silica glass.

Impact of Glass Free Volume on Femtosecond Laser-Written Nanograting Formation in Silica Glass.

In this study, we investigate the effects of densification through high pressure and temperature (up to 5 GPa, 1000 °C) in the making of nanogratings in pure silica glass, inscribed with femtosecond laser. The latter were monitored through retardance measurements using polarized optical microscopy, and their internal structure was observed under scanning electron microscopy. We reveal the difficulty in making nanogratings in densified silica glasses.

Paramagnetic Point Defect in Fluorine-Doped Silica Glass: The E^{'}(F) Center.

Fluorine-doped silica is a key material used in all low-loss and/or radiation-resistant optical fibers. Surprisingly, no fluorine-related radiation-induced point defects have been identified. By using electron paramagnetic resonance, we report the first observation of F-related defects in silica.

Probing densified silica glass structure by molecular oxygen and E' center formation under electron irradiation.

This study aims to learn more about the structure of densified silica with focus on the metamict-like silica phase (density = 2.26 g/cm) by examining the formation of E' point defects and interstitial molecular oxygen O by 2.5 MeV electron irradiation.