Investigation of D 2 O-laser emission at 50, 66, 83, 111, and 116 µm

A D 2 O laser oscillator axially pumped by a TEA CO 2 laser operating on the 9P(32) line has been investigated. The laser emits five FIR lines whose emission characteristics are presented. For the three strongest lines (66, 111, and 116 μm) and an oscillator of length 45 cm, a single axial mode can be made to dominate. Special attention is drawn to the newly discovered and identified 111 μm line.