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Ultrasensitive Surface Spectroscopy With a Miniature Optical Resonator



A C. Pipino


The number density and orientation of molecules at a surface can be probed with extremely high sensitivity by employing a miniature total-internal-reflection-ring cavity in a novel realization of the cavity ring-down optical absorption technique. The modes of the ultra-low-loss cavity, which are excited by photon tunneling, have long lifetimes that are sensitive to the presence of absorbing species in the evanescent field near a civity facet. The TIR-ring cavity forms the basis for a new chemical sensing technology that extends civity ring-down spectroscopy to surfaces, films, and liquids.
Physical Review Letters


absorption, cavity ring-down, evanescent wave, minicavity, single molecule, spectroscopy


Pipino, A. (1999), Ultrasensitive Surface Spectroscopy With a Miniature Optical Resonator, Physical Review Letters, [online], (Accessed April 23, 2024)
Created October 1, 1999, Updated February 17, 2017