Harmonic saturated spectroscopy for improved atomic detection.
A novel method for improved cw laser-induced atomic fluorescence detection that we call harmonic saturated spectroscopy takes advantage of the nonlinear response of an optically saturated atomic system to reject background sources of interference. A reduction in background and an improved SNR are demonstrated for sodium detection in an air-acetylene flame. The dependence of the harmonic signal on intensity, excitation waveform, and depth of modulation was also investigated.
Frueholz
R P
RP
Gelbwachs
J A
JA