Multiple Waveguides Fabricated Simultaneously by Femtosecond Laser Pulses Inside Fused Silica Glasses Using a Multiple Foci Approach

The fabrication of waveguides inside transparent media using ultrashort laser pulses has gained a lot of interest during the past years. When femtosecond laser pulses are focused inside the bulk of transparent materials, the refractive-index change can be induced around the focal volume. Usually, only one waveguide was produced by the femtosecond laser when the sample moved one time. In this paper, we demonstrate that multiple waveguides can be fabricated simultaneously by femtosecond laser pulses using a multiple foci approach inside fused silica glasses. It is realizable for placing an array of slits before the focusing system to control the spatial distribution of laser pulses. The femtosecond laser beam is split by the array of slits and simultaneously focused at different areas by a microscope objective.