Modeling planar leaky optical waveguides

Abstract

A simple theoretical model is proposed for a description of light propagation in ion-implanted leaky waveguides. It permits interpretation of existing published experimental results. A single parameter, the imaginary component of the refractive index, is sufficient to describe losses in the barrier. Simple analytical expressions are obtained for both the lateral resonance condition and the confinement coefficient. For each quasiguided mode, we calculate an optimal barrier thickness which gives the lowest attenuation coefficient. Interestingly, for thick barriers, high-order modes give the best confinement coefficient. Our approach can also describe prism-loaded slab type waveguides.

Reconstruction of refractive index profiles of 3 MeV O2+ion-implanted MgO-doped LiNbO3using wet etching and ellipsometry

“…In addition, the waveguide dimensions could be easily managed by accurate control of both depth and lateral concentrations of the implanted atoms [5,6]. Up to now, implantations of many different ions with various energies (ranging from hundreds of keV to tens of MeV) and doses have been applied to produce waveguides, in both planar and channel cases, in LN crystals [7,8]. In the fabrication of waveguide structure in MgO-LN, diffusion and the ion exchange technique are usually employed [9][10][11].…”

Analysis and Determination of Refractive Index Profiles of O 2+ Ion-Implanted LiNbO 3 Planar Waveguide Using Etching and Ellipsometry Techniques

“…Up to now, implantation of many different ions with various energies (ranging from hundreds of keV to tens of MeV) and doses has been applied to produce waveguides, in both planar and channel cases, in LiNbO 3 crystals. [3,4] For practical applications of the waveguides, precise determination of refractive index profiles (RIP) would be especially important to determine the guiding property of the waveguides. Therefore, many attempts have been put forward to reconstruct the RIP according to the measured mode indices or in-tensity distributions, and several methods have been presented, such as the inverse Wentzel-Kramers-Brillouin approximation method, [5] RCM, [6] BPM, [7] PIPR method, [8] ICM, [9] etc.…”