Investigation of a planar optical waveguide in 2D PPLN using helium implantation technique.

In this work, we report the investigation of a planar waveguide in a 2D periodically-poled lithium niobate (PPLN). The waveguide is fabricated by helium (He(+)) implantation at 2 MeV and a fluence of 1.5 x 10(16) ions/cm(2). Second harmonic generation (SHG) at 532 nm using a Q-switched laser and a CW laser diode at 1064 nm, was measured as a function of angular distribution and temperature. The experimental results show higher gain in SHG conversion efficiency in the waveguide than in the bulk 2D PPLN. In particular, SHGs from 2D reciprocal lattice vectors (RLV) are observed and studied.

Symmetric profile beams from waveguides with asymmetric grating couplers.

An accurate method to analyze integrated optics waveguides with a grating is used to design diffractive gratings. A novel approach to produce symmetric diffracted beams is proposed. In this approach, we vary the grating duty cycle along the propagation direction. We demonstrate that this method results in symmetrical diffracted beam profiles.

Analytical solution for a linearly graded-index-profile planar waveguide.

An analytical solution is presented for the TE modes of a planar waveguide structure comprising a high-index guiding layer and a buried layer with a profile such that the square of the index varies linearly and matches the substrate and high-index guiding layer. The electric-field profiles and the dispersion relation are obtained and discussed, and a solution by the WKB method is compared.

Modal study of GaAs waveguides with zinc-diffused boundaries.

Single-mode planar channel waveguides are produced by zinc diffusion in GaAs. A Zn-doped spin-on-glass (glass forming solution) is used as the diffusion source. The modal behavior of the fabricated waveguides is experimentally investigated. A simple model is used to analyze these waveguides.