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Unique electronics are needed to generate plasmas in a laboratory setting:
One way to generate a plasma in vacuum is to flow high current through a tungsten filament will cause it to emit electrons and it will glow, much like an old light bulb. This dusty plasma experiment used this method to study electrostatic dust charging and lofting.
To generate a plasma at higher pressures, the breakdown voltage of your gas must be exceeded in order to liberate electrons for ionization processes. These free electrons will excite the molecules, and different gases will emit different wavelengths proportional to the energy transitions back to the ground state.
CO2 plasma!
He plasma!
Some considerations: For air at atmospheric pressure, 30 kV per cm is required to initiate dielectric breakdown! This can be achieved with a number of power supplies, including DC, AC, and nanosecond pulsed power. Most high-voltage systems must be well-grounded and shielded considering the significant effect of electromagnetic interference (EMI) on other nearby electronics (we have fried a few keyboards and computer “mice".) Impedance matching of the load, cables, and diagnostic tools is important for protecting the equipment!
Plasmas also need unique diagnostic systems to measure key metrics like the average electron temperature, the electron energy distribution function, the delivered power to the plasma etc. This video shows the wiring and building of a Langmuir probe, which applies a bias voltage to the circuit in order to attract/repel electrons in the plasma and measure current!
