Monomode channel waveguide in KTiOPO_4 crystal produced by Rb~+ ion exchange combined with Si~+ ion implantation

摘要

A novel ion exchanged channel KTiOPO_4 waveguide formation technique is introduced, which can avoid a metal mask being dissolved in an ion exchanged molten salt. Rb~+ ion exchange (340℃, 30 min) was first applied to a KTP sample to produce a planar waveguide substrate, and then Si+ ion implantation (3.0 MeV and 1.5 MeV with doses of 1 × 10~(15) ions/cm~2 and 6 × 10~(14) ions/cm~2, respectively) was carried out to construct channel stripes on the planar waveguide surface that has been deposited by a specially designed photoresist mask. The two-dimensional cross sectional refractive index profile of the channel waveguide was reconstructed by considering the shape of the channel waveguide as well as the index distribution of the planar waveguide.