Near-infrared absorption detection in picolitre liquid volumes using amplified fibre loop ring-down detection

作者：Andrews Nicholas L P; Litman Jessica; Stroh Daniel; Barnes Jack A; Loock Hans Peter^*

来源：Optical Fiber Technology, 2013, 19(6): 822-827.

DOI：10.1016/j.yofte.2013.07.012

• Cavity ring-down
• Absorption spectroscopy
• Fiber (fibre) loop
• Acetylene gas detection
• Liquid sensing
• Picoliter (picolitre) volume

Cavity ring-down spectroscopy is performed using a single-mode fibre loop as an optical cavity. The loop contains absorption cells for either liquids or gases, as well as an erbium-doped fibre amplifier. The fibre amplifier is gain-clamped using a second fibre-loop. Ring-down times can be tuned to permit several hundred roundtrips by adjusting the loss ratio between the two nested loops using a variable optical attenuator. Ring-down measurements were performed either in the time domain or using phase shift measurements. %26lt;br%26gt;Acetylene gas was detected through a ro-vibrational absorption line of the nu(1)-nu(3) combination band at 1532 nm at a limit of detection of 50 ppm. Liquid 1-octyne and 1-dodecyne were detected in a 1 pL volume at detection limits of similar to 20% dilution in dodecane through their C-H stretch vibrational overtone transition.

• 出版日期2013-12