Two-Photon Pumping of a Four-Level System in Ammonia to Obtain 12.16 mu m Radiation for Isotope Separation

Radiation at 12.16 mu m (822.65 cm/sup -1/) has been obtained from /sup 14/NH/sub 3/ using the 2upsilon/sub 2/a(53) to upsilon/sub 2/s(63) transition with the upper level pumped from Ga(33) via upsilon/sub 2/s(43) by two CO/sub 2/ TEA lasers. In an unoptimized cavity, efficiency was 1%: 0.5 mJ of 12.16 mJ out with 50 mJ of input (25% P/sub 9/(8) /sup 13/CO/sub 2/ and 75% P/sub 9/(24) /sup 12/CO/sub 2/). This particular wavelength is relevant to LIS of uranium.