Interfacial Dzyaloshinskii-Moriya Interactions in Layered HM/GdCo/HM Samples

Recent studies have shown that Dzyaloshinskii-Moriya interactions (DMI) play an important role in domain wall formation and motion as well as skyrmion stabilization. Quantitative measurements of the DMI for new material systems are needed to improve our understanding of how to optimize material parameters for applications such as spintronics. Current work establishes Brillouin light scattering (BLS) measurements of surface spin waves as one of the best available methods to measure the DMI. The DMI leads to a difference in the energy of surface spin waves with opposite propagation directions, which gives rise to a frequency shift that can be measured by BLS, a technique that is based on the inelastic scattering of light from spin waves. In this talk I will discuss how we have used BLS to measure the surface spin wave frequencies and compute the DMI of magnetic GdCo samples layered between heavy metals iridium (Ir) and platinum (Pt). By changing the angle of our sample with respect to the BLS probe laser we can select different wave vectors k. Fits to the frequency shift for the two spin wave directions as a function of k provide a quantitative measurement of the interfacial DMI for these samples.