Writing buried optical waveguides: Contrasts in ultrafast and ultraviolet lasers

Abstract

Ultrafast lasers and deep-ultraviolet F2 lasers present stark contrasts in driving multi-photon and single-photon interactions within transparent glasses. Low-loss single mode waveguides and simple photonic components were formed with a 50-fs Ti:Sapphire laser and a 157-nm 15-ns F2 laser inside the bulk of fused silica. Laser interactions were confined by large NA optics within a small ∼8-μm diameter focal volume and scanned with precision motion stages to shape 3-dimensional photonic structures. Refractive index changes of up to 0.01 were induced with the ultrafast laser at a high scanning speed of several hundred microns per second and 100-kHz repetition rate. Weaker refractive index changes of 0.0005 were generated by the F2 laser, owing to a lower 100-Hz repetition rate and weaker absorption in the focal volume. The laser-generated waveguides offer high transmission of ∼1 dB/cm, are transparent to light in the visible and infrared spectrum, and can support multi-mode guiding with low insertion loss into optical fibers. The paper will present examples of fabricating simple three-dimensional photonic components.Ultrafast lasers and deep-ultraviolet F2 lasers present stark contrasts in driving multi-photon and single-photon interactions within transparent glasses. Low-loss single mode waveguides and simple photonic components were formed with a 50-fs Ti:Sapphire laser and a 157-nm 15-ns F2 laser inside the bulk of fused silica. Laser interactions were confined by large NA optics within a small ∼8-μm diameter focal volume and scanned with precision motion stages to shape 3-dimensional photonic structures. Refractive index changes of up to 0.01 were induced with the ultrafast laser at a high scanning speed of several hundred microns per second and 100-kHz repetition rate. Weaker refractive index changes of 0.0005 were generated by the F2 laser, owing to a lower 100-Hz repetition rate and weaker absorption in the focal volume. The laser-generated waveguides offer high transmission of ∼1 dB/cm, are transparent to light in the visible and infrared spectrum, and can support multi-mode guiding with low insertion loss in...