Standalone Integrated Magnonic Devices

Abstract

In the race toward “beyond 6G” telecommunication platforms, magnonics emerges as a promising solution. To date, however, the requirement for bulky external sources of the magnetic bias field necessary for spin wave propagation has constituted a significant bottleneck, impeding the integration of magnonic devices into RF systems. Here, the first demonstration is presented of a standalone and tunable magnonic device featuring all‐electric input and output, fully integrated on a silicon substrate, with a compact footprint of 100 × 150 µm². The device consists of a CoFeB waveguide equipped with two radio frequency antennas, flanked by a symmetric configuration of magnetic flux concentrators and SmCo permanent micromagnets. By varying the distance D between the flux concentrators and the permanent magnets from 0 to 12 µm, the transverse bias field can be tuned from 20.5 to 11 mT, respectively. This variation directly modulates the dispersion relation of Damon‐Eshbach spin wave modes in the CoFeB waveguide. In the proof‐of‐concept devices, the spin wave frequency band ranges from 3 to 8 GHz, with precise tuning of the phase shift up to 120 deg at 6 GHz. The operational frequency band can be easily pushed to higher frequencies through micromagnet engineering.