Oleksandr Stepanenko

Highly Confining Proton Exchanged Waveguides on Z-Cut LiNbO 3 With Preserved Nonlinear Coefficient

We propose a new proton exchange process to reproducibly realize on lithium niobate highly confining (δne = 0.1) planar waveguides without degrading the nonlinear coefficient of the crystal. Waveguides were fabricated with different acidic baths and the crystallographic changes, the index profiles and the local SHG response were measured. We show that for certain fabrication conditions, characteristic of the so-called high-index soft proton exchange process, the high-index modification can be obtained without degrading the crystal nonlinear coefficient. This result should open the way to the fabrication of very efficient nonlinear devices.

Enhanced second-harmonic generation from magnetic resonance in AlGaAs nanoantennas

We designed cylindrical AlGaAs-on-aluminium-oxide all-dielectric nanoantennas with magnetic dipole resonance at near-infrared wavelengths. Our choice of material system offers a few crucial advantages with respect to the silicon-oninsulator platform for operation around 1.55μm wavelength: absence of two-photon absorption, high χ(2) nonlinearity, and the perspective of a monolithic integration with a laser. We analyzed volume second-harmonic generation associated to a magnetic dipole resonance in these nanoantennas, and we predict a conversion efficiency exceeding 10-3 with 1GW/cm2 of pump intensity.

Proceedings of SPIE - The International Society for Optical Engineering

We designed cylindrical AlGaAs-on-aluminium-oxide all-dielectric nanoantennas with magnetic dipole resonance at near-infrared wavelengths. Our choice of material system offers a few crucial advantages with respect to the silicon-oninsulator platform for operation around 1.55μm wavelength: absence of two-photon absorption, high χ(2) nonlinearity, and the perspective of a monolithic integration with a laser. We analyzed volume second-harmonic generation associated to a magnetic dipole resonance in these nanoantennas, and we predict a conversion efficiency exceeding 10-3 with 1GW/cm2 of pump intensity.

Crystallographic and Optical Properties of Z-Cut High Index Soft Proton Exchange (HISoPE) LiNbO 3 Waveguides

Highly confining nonlinear optical waveguides are extremely interesting for highly efficient and ultracompact nonlinear and/or electro-optical devices. In this paper, we concentrate on correlations between structural and optical properties of channel waveguides on z-cut lithium niobate fabricated using a new waveguide fabrication method, we call HISoPE for high index soft proton exchange, which allows obtaining a guiding layer presenting an index increase as high as 0.1 and a nonlinear coefficient equal to its value in the bulk.

Nonlinear effects in Lithium Niobate proton exchanged embedded waveguides

We present preliminary results for embedded waveguides realized on LiNbO3 by a combination of direct and reverse proton exchange. A conversion efficiency of 40%W-1cm-2 can be improved up to 160%W-1cm-2 by a correction of the waveguides imperfection.