An experimental study of ferrite-core driven inductively-coupled low-pressure plasmas

We report on the properties of a ferrite-core driven radio-frequency inductively-coupled plasma. The ferrite core enhances field density for enhanced plasma coupling and improved plasma confinement and focusing. Ferromagnetic-enhanced plasma applicators have been used previously in applications ranging from fusion devices to lighting. Our interests are in furthering this construction to drive continuous and quasi-continuous inductive plasma thrusters for space propulsion applications. Here, we present initial observations of the plasma structure and compare this to simplified models and simulations. We use high frequency 10 MHz videography using an intensified high-speed camera to capture spatial-temporal global plasma behavior, and optical emission spectroscopy to estimate plasma properties while varying gas pressure, composition, and input power.