Slab waveguides were fabricated in Er-doped tungsten-tellurite glass and CaF₂ crystal samples via ion implantation. Waveguides were fabricated by implantation of MeV energy N⁺ ions at the Van de Graaff accelerator of the Research Institute for Particle and Nuclear Physics, Budapest, Hungary. Part of the samples was annealed. Implantations were carried out at energies of 1.5 MeV (tungsten-tellurite glass) and 3.5 MeV (CaF₂). The implanted doses were between 5 x 10¹² and 8 x 10¹⁶ ions/cm². Refractive index profile of the waveguides was measured using SOPRA ES4G and Woollam M-2000DI spectroscopic ellipsometers at the Research Institute for Technical Physics and Materials Science, Budapest. Functionality of the waveguides was tested using a home-made instrument (COMPASSO), based on m-line spectroscopy and prism coupling technique, which was developed at the Materials and Photonics Devices Laboratory (MDF Lab.) of the Institute of Applied Physics in Sesto Fiorentino, Italy. Results of both types of measurements were compared to depth distributions of nuclear damage in the samples, calculated by SRIM 2007 code. Thicknesses of the guiding layer and of the implanted barrier obtained by spectroscopic ellipsometry correspond well to SRIM simulations. Irradiationinduced refractive index modulation saturated around a dose of 8 x 10¹⁶ ions/cm² in tungsten-tellurite glass. Annealing of the implanted waveguides resulted in a reduction of the propagation loss, but also reduced the number of supported guiding modes at the lower doses. We report on the first working waveguides fabricated in an alkali earth halide crystal implanted by MeV energy medium-mass ions.

Date Published: 17 May 2010
PDF: 12 pages
Proc. SPIE 7719, Silicon Photonics and Photonic Integrated Circuits II, 77190G (17 May 2010); doi: 10.1117/12.854624

Published in SPIE Proceedings Vol. 7719:
Silicon Photonics and Photonic Integrated Circuits II
Giancarlo Cesare Righini, Editor(s)