CHAOS IN POLISHED AND ROUGHENED YIG SPHERES

We have studied quasi-periodic and chaotic auto-oscillations in the ferromagnetic resonance of polished and roughened YIG spheres between 2.0 and 3.6 GHz. Regions of quasi-periodicity, steady chaos, transient chaos and intermittency were maped out. The average times for transient chaos follow a scaling law in microwave power. Roughened samples show a greater variety of responses. Changes were also noted in the Fourier spectrum of chaos. The information dimension of the chaos in both types of sample was 3.3 ± 0.2