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arXiv · 1806.06138

Femtosecond laser inscription of nonlinear photonic circuits in Gallium Lanthanum Sulphide glass

María Ramos Vázquez·Belén Sotillo·Stefano Rampini·Vibhav Bharadwaj·Behrad Gholipour·Paloma Fernández·Roberta Ramponi·Cesare Soci·Shane M. Eaton
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Abstract

We report on femtosecond laser writing of single mode optical waveguides in chalcogenide Gallium Lanthanum Sulphide (GLS) glass. A multiscan fabrication process was employed to create waveguides with symmetric single mode guidance and low insertion losses at 800 nm wavelength, compatible with Ti:Sapphire ultrafast lasers. {\mu}Raman and X-Ray microanalysis were used to elucidate the origin of the laser-induced refractive index change in GLS. Nonlinear refractive index measurements of the waveguides were performed by finding the optical switching parameters of a directional coupler, demonstrating that the nonlinear properties were preserved, evidencing that GLS is a promising platform for laser-written integrated nonlinear photonics.

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María Ramos Vázquez, Belén Sotillo, Stefano Rampini, Vibhav Bharadwaj, Behrad Gholipour, Paloma Fernández, Roberta Ramponi, Cesare Soci, Shane M. Eaton. 2018-06-15. Femtosecond laser inscription of nonlinear photonic circuits in Gallium Lanthanum Sulphide glass. https://doi.org/10.1088/2515-7647%2Faade60

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