Low power magnonic devices enabled by monolithic magnetic MEMs integration

Spin waves offer several attractive properties for the development of innovative microwave devices [1], such as scalability, frequency tunability, potential non-reciprocal and non-linear behaviours. Here, we present our works towards the development of magnonic analog microwave devices. We will first present our strategy to optimize their microwave properties, taking the example of magnonic delay lines. Via a combination of analytical models [2], numerical models and measurements via propagative spin wave spectroscopy (PSWS) using Vector Network

Analyzers (VNA), we can successfully optimize their frequency operation, bandwidth and insertion losses. In a second part, we present a strategy to achieve reconfigurable on-chip

magnonic delay lines based on MEMS (Micro-Electro-Mechanical Systems) technology [3]. For this purpose, we developed a process allowing the monolithic integration of magnetic MEMS on a YIG delay line. The magnetic MEMS membrane is suspended above the YIG delay line in the form of a “bridge”. By applying a voltage between the magnetic MEMS

membrane and an electrode placed onto the surface of the magnonic medium, one can move the magnetic MEMS closer to the YIG surface. The stray field experienced by the YIG is hence locally modified by a few mT, thus changing the spin wave group velocity. First characterization of such effect was performed by PSWS, effectively demonstrating propagation delay tunability (signal phase shift) with virtually zero stand-alone power. Such approaches hold promising opportunities for the optimized development of reconfigurable, integrated and low-power magnonic devices.