Fig. 2: Pattern generation from time series.

a–c Representatives of experimentally measured time series at \({I}_{{\rm{dc}}}\) = 12.6, 13.2, and 14.0 mA. The black dots with dotted lines indicate the core-polarity switching events. We normalized the time axes \(t{f}_{0}\) which is identical with a number of core gyrations. The yellow, blue, and red regions indicate waveform patterns denoted by \(pn=-2,-1, {\mathrm{{and}}} +2\), respectively, where \(p\) is a core polarity and \(n\) is a required gyration number for the core-polarity switching. d–f Time evolutions of a required gyration number for the core switching, \(n=\Delta t{f}_{0}\), obtained from a–c by calculating intervals between the black dots. g Schematics of the possible core-polarity switching scenarios. The core trajectories (top panels) and expected output waveforms (bottom panels) are shown for different \(p\) and \(n\) combinations. The colours of the oscillatory patterns (red, blue, and yellow) correspond with those in a–c.