A chemically driven visible laser transition using fast near-resonant energy transfer

Evidence is obtained which demonstrates the potential for developing purely chemical visible lasers based on rapid near-resonant energy transfer from metastable excited triplet states of germanium and silicon monoxide (a/sup 3/ Sigma /sup +/,b/sup 3/ Pi ) to select metal atoms. In this study, the Group IIIA metal atoms were chosen as the energy receptors for the energy transfer-pump sequence. Excited triplet states were generated from the Ge-O/sub 3/, Ge-N/sub 2/, Si-N/sub 2/O, and Si-NO/sub 2/ reactions; the bulk of the experimental results was obtained with a germanium-based system. The energy stored in the long-lived triplet states is transferred to pump X/sup 2/P/sub 1/2/ thallium, indium, and gallium atoms to their lowest lying /sup 2/S/sub 1/2/ states. The authors observe a system of temporal behavior which suggests the creation of a population inversion producing a gain condition and forming the basis for full cavity oscillation on the Tl 7/sup 2/S/sub 1/2/-6P/sub 3/2/ transition at 535 nm.< >