Broadband Ferromagnetic Resonance Using Coplanar Waveguides

Many schemes to exploit the spin of the electron involve microscale or nanoscale ferromagnets. Ferromagnetic resonance (FMR) is a powerful probe of the magnetic properties of magnetic materials. For many applications multi-frequency operation is desirable; however, conventional FMR operates at a fixed frequency. We present a broadband FMR detection scheme based on coplanar wave guides. Increasing the sensitivity of the FMR experiment will permit the study of micron and nano-sized ferromagnets, such as ferromagnetic nanowires.\footnote{S. Pignard, \textit{et al.}, ``Ferromagnetic Resonance in Submicron Metallic Wires,'' \textbf{IEEE Transactions on Magnetics}, Vol. 36, No. 5, pp. 3482 -- 3484, September 2000.} Understanding nanomagnetic structures is significant not only to fundamental physics, but for potential applications such as high density magnetic storage.