High-resolution infrared spectroscopic methods

Jet-AILES apparatus - Tune-up of the High-resolution FTIR spectrometer in Rennes’ laboratory.

Several instruments are employed to probe molecular edifices produced in our reactors (plasma source, high enthalpy source,…) or formed and cooled in continuous supersonic jets.

A high resolution FTIR spectrometer (Bruker IFS125HR) is coupled to Laval nozzles or slit free jets to maximize the absorption column density.

A second instrument, dubbed Jet-AILES, has been developed in collaboration with PhLAM, MONARIS, and AILES beamline from the SOLEIL synchrotron facility. The instrument is implemented on the AILES beamline which is designed for absorption spectroscopy and can produce a far-infrared (15 – 1000 μm) beam up to 30x brighter than conventional sources.


Jet-AILES apparatus - Jet-AILES apparatus on the SOLEIL synchrotron facility

More recently, we have developed in collaboration with LIPhy a Cavity Ring Down Spectrometer (CRDS) to probe trace species generated in our reactors. This ultra-sensitive instrument which covers the 1.50 – 1.68 μm near infrared window is based on optical properties of high Finesse cavities that enhance the interaction path length up to several kilometers in a one-meter-sized cell.