Investigation of Electromagnetic Feedthrough in Spin Wave Based Majority Gates

This paper presents the simulation and experimental investigation of the direct electromagnetic coupling between the four U-shaped antennas of a spin wave majority gate (SWMG). A shielded and unshielded layout are investigated. The layouts are designed to be processed on yttrium iron garnet (YIG) films grown on gadolinium gallium garnet (GGG). The relative permittivity of the GGG substrate is extracted from experimental data as <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\varepsilon r=13$</tex>) with a loss tangent of 0.15 at 10 GHz. Using surface current density simulated results and S parameter measured results we show that the unshielded layout is the suggested approach for future SWMG developments.