Nitrogen laser

A nitrogen laser is a gas laser operating in the ultraviolet range (typically 337.1 nm) using molecular nitrogen as its gain medium, pumped by an electrical discharge.

The wall-plug efficiency of the nitrogen laser is low, typically 0.1% or less, though nitrogen lasers with efficiency of up to 3% have been reported in the literature. The wall-plug efficiency is the product of the following three efficiencies:

• electrical: TEA laser
• gain medium: This is the same for all nitrogen lasers and thus has to be at least 3%
  • inversion by electron impact is 10 to 1 due to Franck–Condon principle
  • energy lost in the lower laser level: 40%
• optical: More stimulated emission than spontaneous emission