Formation of Nanogratings on the Surface of Nanoporous Glass Irradiated by Femtosecond Visible Laser Pulses

Periodic nanostructures with a period of about 100–150 nm are formed on the surface of nanoporous silicate glass irradiated by sharply-focused laser pulses with a wavelength of 515 nm and a duration of 300 fs and are visualized by scanning electron microscopy. The reflection/transmission spectroscopy of the formed nanostructures in the visible range reveals their antireflection effect.