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Monolithic Folded Resonator for Evanescent Wave Cavity Ringdown Spectroscopy



A C. Pipino


An optical resonator is characterized that employs both ultra-high-reflective coated surfaces and total-internal reflection to enable cavity ring-down spectroscopy of surfaces, films, and liquids. The monolithic design possesses a polarization-independent finesse which allows polarization-dependent phenomena, such as molecular orientation, to be probed. Although a restricted bandwidth ({approximately equal to} 80 nm) results from the use of optical coatings, the resonator provides high-sensitivity, excellent stability, and facile operation for narrow bandwidth applications. A noise equivalent absorption of 6.4 x 10-7 Hz-1/2 was obtained using multimode excitation at 530 nm. Improvements in sensitivity of 10 to 104 appear feasible, depending on the spectral region.
Applied Optics
No. 9


cavity ring-down, condensed matter, optical absorption, surfaces, thin films


Pipino, A. (2000), Monolithic Folded Resonator for Evanescent Wave Cavity Ringdown Spectroscopy, Applied Optics, [online], (Accessed June 14, 2024)


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Created March 1, 2000, Updated February 17, 2017