Nanoaperture-enhanced fluorescence

In order to understand the physical phenomena behind nanoaperture-enhanced fluorescence, investigating an isolated nanoaperture is of major interest, which eliminates any effects of aperture coupling. Further, data from a single molecule may reveal information hidden by ensemble measurements, such as variances in kinetic rates, memory effects, or transient states (52). 

Moreover, the studies on nanoaperture-enhanced fluorescence point out that for a properly tailored aperture, count rates per molecule greater than a few hundred thousands photons per second were readily obtained, whereas for a single molecule in open solution, fluorescence saturation prevents the count rate from exceeding a few tens of kilocounts per second. This allows for fast and reliable screening for single molecules. 

In summary, we have tried to overview the state of the field of nanoaperture enhanced fluorescence. While much is known currently about the photophysics of an isolated aperture, it is clear that much more work needs to be performed in order to understand, and maximize, fluorescence enhancement effects from arrangements of apertures and structured apertures. In particular, the relative contributicms of radiative and non-radiative processes have (Hily beoi studied in a couple of experiments, and limited computaticHial work has been performed. In addition, the role of emission directicHiality is not clear at present and requires further study. 

G6rard, D., Wenger, J., Bonod, N., Popov, E., Rigneault, H., Mahdavi, F., Blair, S., Dintinger, J., and Ebbesen, T. W. (2008). Nanoaperture-enhanced fluorescence Towards higher detection rates with plasmonic metals. Phys. Rev. B 77 045413. 

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