Bright Unidirectional Fluorescence Emission of Molecules in a Nanoaperture with Plasmonic Corrugations

Abstract

Controlling the fluorescence emission from nanoscale quantum emitters is a key element for a wide range of applications, from efficient analytical sensing to quantum information processing. Enhancing the fluorescence intensity and narrowing the emission directivity are both essential features to achieve a full control of fluorescence, yet this is rarely obtained simultaneously with optical nanoantennas. Here we report that gold nanoapertures surrounded by periodic corrugations transform standard fluorescent molecules into bright unidirectional sources. We obtain enhancement factors of the fluorescence count rate per molecule up to 120 fold simultaneously with a directional emission of the fluorescence into a narrow angular cone in the direction normal to the sample plane. The bright emission and narrow directionality enable the detection of single molecules with a low numerical aperture objective, and improve the effectiveness of fluorescence-based applications. We thoroughly quantify the increased light-matter coupling as well as the radiation pattern intensity. These results are highly relevant for the development of single molecule sensing, single-photon sources, and light emitting devices.

FRET Enhancement in Aluminum Zero‐Mode Waveguides

“…The time interval for fit is set to ensure that more than 85% of the detected count events are taken into account in the region of interest. As shown already in some of our earlier work [40,45,48] and by the results in Fig. 2a, a single exponential fit is a satisfactory approximation to the fluorescence decay traces in nanoapertures (Fig.…”

Accelerated single photon emission from dye molecule-driven nanoantennas assembled on DNA

“…Therefore, while single particles induce stronger fluorescence signal quenching as the distance decreases 13 , dimers exhibit higher count rates for shorter spacings. Dye molecules with low initial quantum yield would allow larger count rate enhancements 10,28 but their initial shorter lifetimes would forbid the measurement of high Γ/〈Γ 0 〉 enhancements as given in Fig. 2.…”

“…2. In practice, experimental estimation of the antenna efficiencies would require knowing precisely the orientation of the DNA linkers in the microchamber or averaged fluorescence correlation spectroscopy measurements 28 .…”

Percolating plasmonic networks for light emission control

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