Smart measurement setup for spin-wave linewidth /spl Delta/H/sub k/

A new setup for measuring spinwave linewidth /spl Delta/H/sub k/ is described. By use of a dielectric resonator instead of a standard waveguide resonator it is possible to realize much higher microwave magnetic fields at the sample position. Due to the smaller size of the resonator and a more efficient field distribution, the necessary microwave power can be reduced by nearly a factor of 300. Therefore, it is possible to measure spinwave linewidth /spl Delta/H/sub k/ up to 20 Oe (1.6 kA/m) with only 20-W microwave power.