Related Experiment Video
Updated: Jun 30, 2025

Building Langmuir Probes and Emissive Probes for Plasma Potential Measurements in Low Pressure, Low Temperature Plasmas
Published on: May 25, 2021
A field programmable gate array based Langmuir probe system for measurement of plasma parameters at 500 kHz in a
C J Hickling1,2, S Hall2, J R Harrison2
1Department of Electrical Engineering and Electronics, University of Liverpool, Brownlow Hill, Liverpool L69 3GJ, United Kingdom.
Abstract:
By utilizing Field Programmable Gate Arrays in a configuration similar to that of the Mirror Langmuir Probe, it is possible to bias a single probe at three precise voltages in sequence. These voltages can be dynamically adjusted in real-time based on the measured plasma electron temperature to ensure the transition region is always sampled. The first results have been obtained by employing this method and have generated real-time outputs of electron temperature, ion saturation current, and floating potential on a low temperature pulsed-DC magnetron at 500 kHz. These results are in good agreement with the analysis of a conventionally swept Langmuir probe. This probe is designed with the intention of being implemented on MAST-U to aid in the study of exhaust physics and enable further investigation into filamentary behavior.
Related Concept Videos
Inductively Coupled Plasma Atomic Emission Spectroscopy: Principle
The ions and electrons produced interact with the fluctuating magnetic field created by a water-cooled...
Inductively Coupled Plasma Atomic Emission Spectroscopy: Instrumentation
There are three main types of inductively coupled plasma atomic emission spectroscopy (ICP-AES) instruments: sequential, simultaneous multichannel, and Fourier transform instruments, with the latter being less commonly used....

