Strip waveguides in Yb3+-doped silicate glass formed by combination of He+ ion implantation and precise ultrashort pulse laser ablation

Abstract

Strip optical waveguides were realized in Yb3+-doped silicate glass with ultrashort pulse laser ablation assisted He+ ion implantation. Planar waveguides were first prepared near the glass surface by He+ ion implantation (450 keV + 500 keV + 550 keV), followed by annealing at 260℃. After that, under the processing parameters of 3 μJ energy and 50 μm/s ablation velocity, two parallel tracks with separation of 15, 20, and 25 μm were, respectively, inscribed on the sample, which confine the light in lateral direction to form a strip waveguide. The near-field intensity measurement indicates that the strip waveguides maintain the single-mode propagation characteristics with 976 nm laser injection, and present the multi-mode characteristics with 632.8 nm laser injection, showing that the guided modes are well supported in the strip waveguides. The minimum propagation loss of strip waveguide is 1.35 dB/cm. Fluorescence emission spectra indicate that the gain properties of waveguide core were maintained well after waveguide preparation, revealing that the strip waveguide device in Yb3+-doped silicate glass has the potential to become an active device as waveguide laser or waveguide amplifier.

Keywords

• strip optical waveguide
• yb3+-doped silicate glass
• ion implantation
• femtosecond laser ablation