Emission of infrared molecular hydrogen lines from a cooled-gas laser

The results are reported of an experimental investigation of the pulsed stimulated emission of the radiation resulting from the 2sσE¹Σ_g⁺–2pσB¹Σ_u⁺ electronic transition in the H₂ molecule. The principal features of this emission were similar to those observed for all other known laser electronic transitions in molecules. In particular, the output power increased strongly when the active gas was cooled. The laser emission was observed in the range of tube voltages V and gas densities N given by the parameter γ=(V–V₀)/N (V₀ is a constant). Cooling of the active gas made it possible to achieve a record, for this type of laser, peak output power of 1.5 kW.