Evaluation of a magnetically coupled microcavity hollow cathode discharge for atomic emission spectroscopy

A magnetically coupled microcavity hollow cathode discharge device was evaluated for its analytical potential as a boosted atomic emission source. A magnetic field using an electromagnet was applied perpendicular to the axis of the microcavity hollow cathode. The intensity of the atomic emission of copper, aluminum and the ionic emission of magnesium increased with increasing magnetic field until it reached a maximum. A further increase in the field strength did not lead to an enhancement of these emissions. The attainment of the maxima was attributed to the increase in the electron temperature and radial diffusion of the electrons from the center of the microcavity axis. Electron temperatures in the presence of the magnetic field calculated based on the semicorona model were shown to be proportional to the square of the reduced field strength. Further, these maxima were correlated to the energies of the upper levels of the transition studied.