Predictions of far-infrared laser lines from ^14NH_3 and ^15NH_3

Abstract

We have used the precise molecular constants of the V(2) vibration of (14)NH(3) and (15)NH (3) together with the accurately known frequencies of the various CO(2) and N(2)O laser lines to calculate the coincidences between pump laser lines and NH (3) absorption lines that could lead to cw FIR laser emission. We have experimentally examined the coincidences between NH(3) absorption lines and (12)C(16)O(2) laser lines, providing information about up to which quantum numbers J, K laser emission can be expected. FIR power measurements confirm the expected good efficiency of NH(3) FIR lasers.