Indirect absorption spectroscopy using quantum cascade lasers: mid-infrared refractometry and photothermal spectroscopy
2013
Article
pf
We record vibrational spectra with two indirect schemes that depend on the real part of the index of refraction: mid-infrared refractometry and photothermal spectroscopy. In the former, a quantum cascade laser (QCL) spot is imaged to determine the angles of total internal reflection, which yields the absorption line via a beam profile analysis. In the photothermal measurements, a tunable QCL excites vibrational resonances of a molecular monolayer, which heats the surrounding medium and changes its refractive index. This is observed with a probe laser in the visible. Sub-monolayer sensitivities are demonstrated. (C) 2013 Optical Society of America
Author(s): | Pfeifer, Marcel and Ruf, Alexander and Fischer, Peer |
Journal: | OPTICS EXPRESS |
Volume: | 21 |
Number (issue): | 22 |
Pages: | 25643-25654 |
Year: | 2013 |
Department(s): | Micro, Nano, and Molecular Systems |
Bibtex Type: | Article (article) |
DOI: | 10.1364/OE.21.025643 |
BibTex @article{ISI:000327007800024, title = {Indirect absorption spectroscopy using quantum cascade lasers: mid-infrared refractometry and photothermal spectroscopy}, author = {Pfeifer, Marcel and Ruf, Alexander and Fischer, Peer}, journal = {OPTICS EXPRESS}, volume = {21}, number = {22}, pages = {25643-25654}, year = {2013}, doi = {10.1364/OE.21.025643} } |