Spontaneous emission enhancement of a single molecule by a double-sphere nanoantenna across an interface

Abstract

We report on two orders of magnitude reduction in the fluorescence lifetime when a single molecule placed in a thin film is surrounded by two gold nanospheres across the film interface. By attaching one of the gold particles to the end of a glass fiber tip, we could control the modification of the molecular fluorescence at will. We find a good agreement between our experimental data and the outcome of numerical calculations.

Dual-channel spontaneous emission of quantum dots in magnetic metamaterials

“…We also find that in contrast to small spherical metal particles, the contribution of higher-order electric moments to the radiative emission properties is substantially increased and even leads to greater PL enhancement factors for the magnetic mode than for the electric dipole mode. This finding also has important implications for the design of plasmonic nanostructures for emission enhancementfor example, in single-molecule and fluorescence-sensing applications 50 . As opposed to small spherical nanoparticles in which higher-order modes are completely dark and can even cause PLquenching, more complex structure designs make higher-order plasmonic modes accessible for PL enhancement, resulting in a more efficient detection of quantum emitters or molecules.…”

“…3a,b show that for y-polarized detection (magnetic mode) the PL-enhancement factors are on average B1.5; however, there are spatial positions where enhancement of up to approximately three can be observed. This is a notable enhancement given that, in contrast to single plasmonic structures 3,40,49 where a precise placement of the emitters is possible 40,41,50 , large PLenhancement factors are harder to realize in metamaterials since, here, the main focus is on the spatially averaged effective response of the coupled QD metamaterial. For this reason, in our experiments and numerical simulations, we average over all possible distances, lateral positions and dipole orientations of the QDs with regard to the split-ring-resonator meta-atom.…”

Emission rate and collection efficiency of photons from single terrylene molecules: Dependency on the substrate and the collection lens

“…The mean values of the radiative decay lifetimes on glass and on SIL are obtained as 19.9 ns and 6.0 ns, respectively. The large error comes from the dependence of the decay lifetime of molecules on the local environment, mainly on the depth of the molecules in the pT crystal [10,14,17,18]. Here we find that molecules placed on SILs can emit roughly three times more photons than those placed on glass.…”

“…As a result, the radiative decay times of single emitters are in the range of 10 −9 ∼ 10 −7 seconds, and * E-mail: kglee@hanyang.ac.kr; Fax: +82-2-2298-0319 non-radiative decay channels can further reduce down the photon flux [1][2][3]. Enhancing the photon emission rate from single emitters is an important issue in nanooptics, and various strategies have been demonstrated theoretically [9] and experimentally [10][11][12]. The photon emission rate, the radiative decay rate, can be enhanced by increasing the local optical density of states (DOS) of emitted photons.…”

On the detection of characteristic optical emission from electronically coupled nanoemitters

“…[1][2][3] Many of the most attractive modern systems operate on the basis of the distinctive dispersion properties and intense plasmonic response of metallic nanoparticles at optical frequencies, and one of the most appealing facets of such systems is their capacity to steer directional emission through nanoantenna-emitter coupling -especially by interface with gold nanoantennas. [4][5][6][7][8][9][10][11][12][13][14][15][16][17] Alongside these developments, a range of other plasmonic and dielectric methods have also been demonstrated to provide for enhanced rates of fluorescence [18][19][20][21][22] and resonance energy transfer, 23,24 from and between nanoscale components. Moreover, there is recent theory work that has identified new opportunities for nonlinear optical techniques to improve data capture in fluorescence microscopy and imaging.…”