Mode selective parametric excitation of spin waves in a Ni81Fe19 microstripe

We present the experimental observation of parallel parametric amplification of selected thermal spin-wave modes in a transversally magnetized Ni81Fe19 microstripe. By employing Brillouin light scattering microscopy, we identify the dominant group, i.e., the spin-wave mode that is preferentially amplified. Due to the existing spin-wave quantization in the system, it is possible to select one specific mode to be parametrically excited by changing the bias magnetic field. This gives access to transversal spin-wave eigenmodes of the stripe which are promising for spin-wave information processing and also to modes localized at the stripe edges.