The radiation of spin waves by rectangular spin-valve elements into a surrounding magnetic film has been studied experimentally using a novel micro-focus Brillouin light scattering setup allowing for spatially resolved measurements of the intensity of dynamic magnetization with a resolution better than 300nm. The investigated elements have lateral dimensions of 1.3×2.3μm2 and consist of a 10nm thick Co80Fe20 and a 5nm thick Ni81Fe19 layer separated by a 4nm thick Cu spacer layer. It was found, that the elements radiate spin waves at frequencies corresponding to their laterally quantized spin-wave eigenmodes. Two-dimensional distributions of intensities of spin waves radiated by different eigenmodes were recorded outside the element. It was shown, that the radiation patterns consist of several rays intersecting each other and forming spots where the amplitude of variable magnetization locally increases. A theoretical model qualitatively explaining the observed radiation patterns has been suggested.
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