Designing Bulk Acoustic Wave Resonators For Parametric Amplification Of Spin Waves

Spintronics is an emerging field of research dealing with devices that can potentially exploit the additional degree of freedom provided by the electron spin along with or instead of the conventional electronic charge. One of the most promising aspects of spintronics is the potential use of magnetostatic spin waves as information carriers in logic devices, where information is encoded in the electron spin. A major obstacle in making this a practically viable alternative to conventional electronics is the very large intrinsic spin wave damping in most known magnetic materials. In this work, we propose a new technique of parametrically amplifying spin waves by means of acoustic resonators. An equivalent electrical model of an acoustic resonator was developed to efficiently design the acoustic resonators for the desired frequency ranges. Backward volume magnetostatic spin waves were measured in Yttrium Iron Garnet films at frequencies of 1.7 GHz or higher, requiring acoustic resonators to be designed for at least 3.4 GHz or higher for parametric amplification. Acoustic resonators with resonance frequency of 4 GHz were fabricated.