atomic laser

A gas laser which is pumped using energy transfer from other atoms or molecules. Examples are the helium-neon ( HeNe ) the copper vapour laser.
PAC, 1995, 67, 1913 (Nomenclature, symbols, units, and their usage in spectrochemical analysis-XV. Laser-based molecular spectroscopy for chemical analysis - laser fundamentals (IUPAC Recommendations 1995)) on page 1919