Laser Writing of Polarization-Sensitive Birefringence in Sodium-Borosilicate Glass

Abstract

It is demonstrated that femtosecond laser pulses can be used to form birefringent microregions in sodium borosilicate glass with the composition 68 SiO₂, 27 B₂O₃, 4 Na₂O, and 1 Al₂O₃ (mol.%); the birefringence is associated with the formation of nanogratings and its slow axis is oriented perpendicular to the polarization plane of the writing laser beam. The dependences of the phase shift of the light passing through these microregions on the number and energy of the laser pulses forming them are determined. It is shown by means of confocal RS spectroscopy that the content of sodium cations decreases in the formed microregions.