Ultrafast laser fabrication of low-loss waveguides in chalcogenide glass with 0.65 dB/cm loss

This Letter reports on the fabrication of low-loss waveguides in gallium-lanthanum-sulfide chalcogenide glasses using an ultrafast laser. Spatial beam shaping and temporal pulse width tuning were used to optimize the guided mode profiles and optical loss of laser-written waveguides. Highly symmetric single-mode waveguides guiding at 1560 nm with a loss of 0.65 dB/cm were fabricated using 1.5 ps laser pulses. This Letter suggests a pathway to produce high quality optical waveguides in substrates with strong nonlinearity using the ultrafast laser direct writing technique.