Extinction measurement with open-path cavity ring-down technique of variable cavity length

Cavity Ring-down Biosensing

Cavity ring-down spectroscopy (CRDS) is an established technique for gases sensing that is newly emerging in the field of optical biosensing. This approach measures changes in the rate of decay of light injected into an optical resonator and relates them to optical loss along its length. This principle has recently been adapted for use in liquids, providing a highly sensitive method for quantit...

Cavity-locked ring-down spectroscopy

Spatial domain realization of the cavity ring-down technique in a plane Fabry–Perot cavity

We propose and demonstrate a spatial version of the cavity ring-down concept in which a photon flux decay is displayed along the spatial coordinate at the exit of a plane Fabry–Perot cavity. The photon decay signals are simulated based on a simple theoretical model combining ray optics and diffraction involved in the spatial ring-down generation, which are found to be in good accordance with th...

Cavity ring-down technique and its application to the measurement of ultraslow velocities.

We have developed a new ring-down technique that does not require a shutter to turn a probe laser on and off. With a rapid cavity scan we can measure a simple exponential cavity decay from which a cavity finesse can be found. When the cavity is scanned slowly, the cavity decay exhibits an amplitude modulation, and an analytic expression is derived for this modulation. With this new technique we...

Saturated-absorption cavity ring-down spectroscopy.

We report on a novel approach to cavity ring-down spectroscopy with the sample gas in saturated-absorption regime. This technique allows us to decouple and simultaneously retrieve the empty-cavity background and absorption signal, by means of a theoretical model that we developed and tested. The high sensitivity and frequency precision for spectroscopic applications are exploited to measure, fo...