Ferromagnetic Resonance and Spin Wave Studies in Permalloy Nanostructures and YIG Films
In this talk I will summarize a somewhat eclectic program of study involving broadband ferromagnetic resonance (FMR) experiments at Northwestern. One portion of the talk will be devoted to describing FMR and spin wave modes in permalloy (Py) thin film nanostructures. In the Py systems one of our motivations is to study structures that are conducive in coupling to specific finite wavelength magnetostatic modes.
In parallel with these studies, we are interested in measuring the FMR spectrum of Py nanostructures with unusual geometries. Specific to this area I will present data recently taken on artificial magnetic quasicrystals and permalloy deposited on top of a colloidal crystal. The second topic of the talk will deal with recent experiments performed where we have excited long wavelength magnetostatic modes in YIG with microwave striplines patterned directly on the YIG. We used spin Hall metal striplines which allow us additional flexibility in spin wave detection. Additionally, we observed an unexpected change in the coupling to magnetostatic spin waves under field reversal or microwave current reversal.