Spontaneous excitation of the dominant mode in a spin-wave active ring -- a self-exciting positive-feedback system incorporating a spin-wave transmission structure -- occurs at a certain threshold value of external gain. In general, the wavenumber of the dominant mode is extremely sensitive to the properties and environment of the spin-wave transmission medium, and is almost impossible to predict. In this letter, we report on a backward volume magnetostatic spin-wave active ring system incorporating a magnonic crystal. When mode enhancement conditions -- readily predicted by a theoretical model -- are satisfied, the ring geometry permits highly robust and consistent forced dominant wavenumber selection.
@article{arxiv.0912.2029,
title = {Magnonic crystal based forced dominant wavenumber selection in a spin-wave active ring},
author = {A. D. Karenowska and A. V. Chumak and A. A. Serga and J. F. Gregg and B. Hillebrands},
journal= {arXiv preprint arXiv:0912.2029},
year = {2012}
}