Absorption spectra, near-field intensity and microscopic cross section of RbTiOPO4 channel waveguide formed by ion implantation

Abstract We report on optical channel waveguide in RbTiOPO4 crystal produced by photographic masking and following direct C3+ ion implantation at 6.0 MeV with a fluence of 5 × 1013 ions/cm2. The absorption spectra show that there are fewer point defects in the waveguide region, forming “crystal waveguide”. The bright near field intensity distribution of the transverse-electric mode indicate that the light can be guided in a well confined way almost without leakage. Considering the Fresnel reflection at the air–crystal interface is about 15%, we obtained a loss of 1.7 dB/cm for the channel waveguide at wavelength of 633 nm.