Femtosecond laser written channel optical waveguide in Nd:YAG crystal

Abstract

Abstract Low-repetition-rate (1 kHz) femtosecond laser inscription is used to fabricate channel waveguides in Nd:YAG crystal. Guiding occurs in the surroundings of the focal spot. End-to-end coupling measurements reveal the near-field intensity distribution of waveguides. The index profile reconstruction, mode analysis performed by the beam propagation method of these waveguides are presented. The waveguide written with 3.0 μJ pulse energy and 100 μm/s scan velocity shows strong guidance at 632.8 nm, and a propagation loss of about 0.5 dB/mm.