Features of Chaotic Spin Waves in Magnetic Film Feedback Rings
The features of chaotic spin waves in magnetic film feedback rings were studied. Experiments made use of an yttrium iron garnet thin film-based active feedback ring. The excitation of chaotic spin waves relied on the three-wave interactions of short- and long-wavelength backward volume spin waves. The features of the chaotic spin waves were evaluated through the calculation of the ambiguity functions (AFs) of the measured signals. The calculation results indicate that one can tune the AF properties of the chaotic spin waves via the ring gain. In particular, an increase in the ring gain leads to the suppression of side lobes in the AF diagram, both in number and amplitude, but produces negligible effects on the main AF peak. The results on cross ambiguity functions are consistent with the chaotic nature of the chaotic spin waves. These results indicate the potential of magnetic film-based chaotic oscillators for chaotic radar applications.
KeywordsSpin Wave Doppler Frequency Side Lobe Signal Duration Yttrium Iron Garnet
This work was supported in part by the U. S. National Science Foundation (DMR-0906489) and the U. S. Army Research Office (W911NF-11-C-0075).
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