A laser-locked cavity ring-down spectrometer employing an analog detection scheme
| Autor: | Robert L. Byer, Benno Willke, Richard N. Zare, Thomas G. Spence, Charles C. Harb, Barbara A. Paldus |
|---|---|
| Rok vydání: | 2000 |
| Předmět: | |
| Zdroj: | Review of Scientific Instruments. 71:347-353 |
| ISSN: | 1089-7623 0034-6748 |
| Popis: | A system is described that employs a diode-pumped Nd:YAG continuous-wave laser source servolocked to a three-mirror optical cavity and an analog detection circuit that extracts the ring-down rate from the exponentially decaying ring-down waveform. This scheme improves on traditional cavity ring-down spectroscopy setups by increasing signal acquisition rates to tens of kilohertz and reducing measurement noise sources. For example, an absorption spectrum of a weak CO2 transition at 1064 nm is obtained in less than 10 s at a spectral resolution of 75 kHz employing a cavity with an empty-cavity ring-down decay lifetime of 2.8 μs and a total roundtrip path length of 42 cm. The analog detection system enables laser frequency scan rates greater than 500 MHz/s. The long-term sensitivity of this system is 8.8×10−12 cm−1 Hz−1/2 and the short-term sensitivity is 1.0×10−12 cm−1 Hz−1/2. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|