Signal Enhancement for Ferromagnetic Resonance Measurement of Magnetic Nanowire array

In this paper, a ferromagnetic resonance (FMR) measurement technique to enhance signal detection of magnetic nanowire in array form (MNA) is presented. Two signal enhancement methods were developed for characterizing the MNA sample. The samples were placed on top of a coplanar waveguide (CPW) test circuit and exposed to both AC and DC magnetic fields. The first method indicates that FMR response is stronger for MNA on the slots due to stronger AC field around slots. The second method indicates that the FMR response of MNA with a copper (Cu) back layer is seven times stronger. Thus, to enhance the signal strength of FMR response, the MNA sample should be placed on the slot and/or include a Cu back layer. These methods are useful for identification methods, such as nanolabels used in biosensing applications that use small volume and size samples.