Polarization-Dependent Birefringence in Lithium Aluminosilicate Glass.

The formation of polarization-dependent birefringence, apparently due to the formation of nanogratings, in the bulk of lithium silicate and lithium aluminosilicate glasses under the action of a series of femtosecond laser pulses was demonstrated. The phase shift in the light passing through the modified regions was determined as a function of the parameters of the laser radiation and the chemical composition of the glass. It is shown that Al2O3 content growth due to the presence of an alkaline component in the glass composition effects an increase in the minimum number of pulses required for the formation of a birefringent region as well as an increase in the retardance. [ABSTRACT FROM AUTHOR]