Active waveguides written in rare-earth doped materials with femtosecond laser pulses

Abstract

Optical waveguides can be fabricated inside various glasses by using tightly focussed femtosecond laser pulses to induce a change in the refractive index. Researchers have shown this direct-write technique has the potential to generate both planar and three-dimensional photonic devices for optical networking applications inside a wide range of materials. In particular, waveguides can be written in Erbium-doped phosphate glass and demonstrate a net gain when used as an active element in a standard waveguide amplifier. We report results of a detailed study optimising the beam delivery configurations and fabricating photonic waveguides and devices in both passive and active glasses.Optical waveguides can be fabricated inside various glasses by using tightly focussed femtosecond laser pulses to induce a change in the refractive index. Researchers have shown this direct-write technique has the potential to generate both planar and three-dimensional photonic devices for optical networking applications inside a wide range of materials. In particular, waveguides can be written in Erbium-doped phosphate glass and demonstrate a net gain when used as an active element in a standard waveguide amplifier. We report results of a detailed study optimising the beam delivery configurations and fabricating photonic waveguides and devices in both passive and active glasses.