Effect of the dielectric medium on vector network analyzer-based spectroscopy of magnetic layers

Spin waves for on-chip information transfer and processing present a promising path toward post-CMOS computing technologies. In this paper, we investigate the unintended artifacts that may arise when exploring the effect of a local electric field on spin wave control through voltage-controlled magnetic anisotropy. Our results reveal changes in the dielectric constant that may be mistaken for direct effects on spin wave dispersion. Our experimental analysis using propagating spin wave spectroscopy, supported by electromagnetic simulations, demonstrates that changes in the detected spin wave signal upon applying a local electric field are of non-magnetic origin. With these findings, we aim to highlight the challenges associated with implementing electric fields in spin wave devices and provide valuable insights for the development of energy-efficient, next-generation computing technologies.