The theory and practical design of a monopole ion trapping system are presented, along with our experimental observations of nonlinear motion of a single charged polyethylene microsphere in the trap. For these observations, the trap was operated at a drive frequency of 70 Hz and easily produced voltages in the kV range. The resulting ion motion was captured using a high-speed camera acquiring images at up to 4000 frames per second. These data yielded time series, phase space portraits, and power spectra of the ion motion in a range of applied voltages, allowing us to observe a period-doubling route to chaos and a period-3 window within the chaotic regime. It is shown that these observations agree with a numerical integration of the ion's nonlinear equation of motion in the monopole electric field.
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See supplementary material at https://www.scitation.org/doi/suppl/10.1119/10.0001958 for examples of the videos we used for data analysis. The videos provided correspond to portions of the Period-1, 2, and 4 data from Fig. 10, and portions of the chaotic data from Fig. 11.
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