Continous emission monitoring using cavity ringdown spectroscopy

摘要

Cavity ringdown spectroscopy (CRS) is a novel, highly sensitive technique for performing absorption spectroscopy using pulsed lasers. In CRS, the rate of light absorption by a sample within a closed optical cavity is measured, rather than theabsorbed signal intensity. The high sensitivity of the CRS method stems from long sample pathlengths and relaxed constraints on the accuracy of the decay rate measurement.The use of cavity ringdown for analytical purposes is a natural extension of previous atomic absorption spectroscopy methods. However, while CRS has rapidly gained popularity among the molecular spectroscopy community, the work reported here concerns thefirst efforts to apply this technique to analytical atomic spectroscopy. In particular, the combination of CRS with a well-established tool for sample atomization, the inductively coupled plasma, may represent a viable technique for on-line, trace levelcontinuous emission monitoring of species such as toxic heavy metals and radionuclides.