Abstract

Diode lasers of the AlGaAs and InGaAsP types are small and easy to operate systems. Their wavelength can be tuned by temperature and by diode current. In particular, the possibility of very rapid tuning by current is important for wavelength modulation spectrometry which allows to suppress the 1/f noise, for example, in absorption measurements. The still limited wavelength range of operation of commercially available laser diodes (625 < λ < 1600 nm) can be partly overcome by frequency doubling of laser radiation (SHG) in non-linear crystals. The power of diode laser wavelength modulation atomic absorption spectrometry (DL-WMAAS) has been demonstrated recently by AAS measurements in graphite tube atomizers¹, analytical flames² and low pressure plasmas³. The present contribution reports on the application of this technique for element selective detection in analytical flames and low-pressure plasmas coupled to HPLC and GC, respectively.

© 1996 Optical Society of America