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arXiv · 2309.13831

Coherent high-frequency axial oscillations in a partially magnetized direct current magnetron discharge

Ryan C. Przybocki·Mark A. Cappelli
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Abstract

High frequency oscillations are observed in a neon plasma of a direct current magnetron discharge. At low discharge currents, we see highly coherent 60 MHz fluctuations. Above a distinct current threshold, secondary 5 - 10 MHz fluctuations emerge in addition to turbulent fluctuations in the 60 - 100 MHz range. The oscillations in the total discharge current suggest axial wave propagation. A lower-hybrid wave theory is invoked to model the high frequency oscillations. We attribute the low frequency modes to a turbulence-driven inverse cascade process, as suggested by recent simulations.

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Ryan C. Przybocki, Mark A. Cappelli. 2023-09-25. Coherent high-frequency axial oscillations in a partially magnetized direct current magnetron discharge. https://arxiv.org/abs/2309.13831

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