Stimulated Emission of Magnetic Dipole Radiation in Electric Discharges*

This paper notes the possibility of producing stimulated magnetic dipole radiation in the near-infrared region in electric discharges. This possibility is due to quite large “naturally” occurring inversion found in electric discharges in gases possessing a metastable state lying above a radiating state to which it can radiate by a magnetic dipole transition. The heavier rare gases and the heavier alkaline earths, especially mercury, offer attractive possibilities. Population measurements of Koedam and Kruithof in mercury, and the simplified calculation presented here, indicate that the required inversions in mercury are within reach.