Spin waves turning a corner

We studied the propagation of spin waves in a Ni81Fe19 micro-waveguide comprising a smooth, S-shaped bend using Brillouin light scattering microscopy. A direct current flowing through a gold wire underneath the Ni81Fe19 provides a local magnetic field, which maintains a transverse magnetization around the bend of the waveguide. It is demonstrated that spin-wave propagation inside the bend can be realized in contrast to the case of an externally applied magnetic field, which generates strong inhomogeneities in the internal effective field distribution, preventing any spin-wave propagation across the bend. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4738887]