Saturated double-resonance emission spectroscopy of lead for sensitive atomic analysis.

Double-resonance laser emission at 283.3 and 600.2 nm was used to excite gas-phase atomic lead present in an electrothermal atomizer. Buffer-gas-induced collisional energy transfer occurs to states as much as 6000 cm(-1) below the highest optically pumped level. Single photons emitted from these states, whose wavelengths are as short as 202.2 nm, were detected. This study illustrates the utility and versatility of the saturated double-resonance technique for ultrasensitive and specific atomic detection (detection limits in the 10(-15)-g range) as well as its potential in atomic-spectroscopy and excited-state-dynamics studies.