Prototypical Square Ring Mini-cavity. The optimum cavity has a footprint smaller than the diameter of a dime. Two prisms couple the mini-cavity to the laser and photo-detector. Eventually fiber-optics will provide this coupling.

Evanescent Wave Ring-down Spectroscopy using a Square Mini-Cavity



Experimental Data

When 630 nm laser light was injected into the square mini-cavity (at left), it produced the ring-down decay curve (on right).

When optimized, we expect this device to exhibit 1/e decay times of about 2 microseconds.
Pellin-Broca Cavity

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