Microcavity

Finally, tlie ability to optically address single molecules is enabling some beautiful experiments in quantum optics. The non-Poissonian photon arrival time distributions expected tlieoretically for single molecules have been observed directly, botli antibunching at short times [112] and bunching on longer time scales [6, 112 and 113]. The fluorescence excitation spectra of single molecules bound to spherical microcavities have been examined as a probe... 

Norris D J, Kuwata-Gonokami M and Moerner W E 1997 Excitation of a single molecule on the surface of a spherical microcavity Appl. Phys. Lett. 71 297-9... 

R. J. Teitel, "Experimental Studies on Microcavity Hydrogen Storage," IrdMiami International Conference on Alternative Energy Sources, Miami Beach, Ha., 1980. 

Mikro-lith, m. microlite. -lunker, n. microcavity, micropore, -mechaaik, /. micromechanics, -meterschraube, /. micrometer screw. 

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U. Lcmmer, R. Hcnnig, W. Guss, A. Oehse, J. Pommcrehne, R. Sander, A. Greiner, R.F. Mahn, H. Bassler, J. Feldmann, E.O. Gobcl, Microcavity effects in a spin-coaled polymer two-layer system, Appl. Phys. Lett. 1995, 66, 1301. 

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Theoretical Analysis of Microcavity-Enhanced Absorption Sensors... 

Consider a microcavity in which light is coupled into a WGM from an adiabatically tapered fiber tangentially in contact with the resonator. Tunable single-frequency... 

Fig. 5.1 Four mirror ring cavity model. Left, microcavity and tapered fiber in contact. Light can couple from the fiber into the resonator and back into the fiber. Right, the four mirror ring cavity equivalent. The top mirror is partially transmitting all others have 100% reflectivity. Reprinted from Ref. 3 with permission. 2008 Optical Society of America...

Microcavity-Enhanced Detection of Atmospheric Trace Gases... 

The broadband analysis was confirmed by the experimental results mentioned in Sect. 5.4.1. This method can also be further enhanced by some of the techniques described in Sects. 5.4.2 and 5.4.3. The conclusion is that these methods of microcavity-enhanced optical absorption sensing provide compact, inexpensive, and sensitive detectors for molecular species in the ambient gas or liquid, and that further increases in sensitivity can be implemented to make them even more competitive. The molecular-transition specificity that is implicit in absorption spectroscopy is a limiting restriction, but the surface-enhanced Raman sensing that is enabled by metallic nanoparticles on the microresonator surface can significantly increase the number of molecular species that could be detected. 

In conclusion, when a WGM is excited in a dielectric microresonator, its evanescent component provides a convenient probe of the microresonator s surroundings. Various ways to implement evanescent-wave sensing have been devised, but the emphasis of this chapter has been on microcavity-enhanced absorption spectroscopy. The techniques described here have broad applicability, can even be used with broadband sources, and lend themselves well to further enhancement methods. We are looking forward to continuing our development of these sensors. 

Rosenberger, A. T., Analysis of whispering gallery microcavity enhanced chemical absorp tion sensors, Opt. Express 2007, 15, 12959 12964... 

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