Magneto-Optic Materials for Integrated Applications

Abstract

AbstractAll of the materials necessary for integrated isolators were grown and the application of 2D photonic crystal structures to isolators has been explored. Magnetooptical garnets were grown monolithically by reactive rf sputtering. MgO was used as a substrate because it will useful for future buffer layers and optical claddings. The chemical, structural, and optical properties of the resulting films were analyzed. In order to incorporate photonic crystal structures into the magneto-optic integration scheme, we have calculated a range of radii and spacings necessary to fabricate YIG/air structures with 2D photonic bandgaps using an advanced plane-wave expansion technique. Selfassembled alumina nanostructures have been grown with similar symmetries as those calculated, namely hexagonal close-packed pores. These nanostructures were grown onto semiconductor and oxide substrates in order to demonstrate their use as RIE masks in fabricating photonic crystals. The nanostructures can also be transferred into YIG using separate alumina masks. However, the actual structures grown in this work were smaller than those required for telecommunications due to power supply limitations. For biasing the magneto-optical elements, sputtering was used to monolithically integrate permanent SmCo magnet films using semiconductor-friendly processing. These magnets were sufficient for biasing our magneto-optical waveguides. The chemical, structural and magnetic properties of these materials, as well as total integration with SiO2 cladding layers were analyzed.