One of the major challenges in nanophotonics is the direct measurement of the interaction of a nanostructure with a single fluorescent emitter at the nanometer level. Several approaches developed to this aim can be found in the literature. Recently, single molecule localization imaging, traditionally used for the study of biological samples, entered the nanophotonics realm opening new horizons. We report on the development of single-molecule fluorescence lifetime imaging microscopy (sm-FLIM), an innovative approach enabling the simultaneous measurement of the lifetime and the intensity of single-molecules densely labeling a nanostructured sample, with a field of view of 10 µm2 , a spatial resolution of approximately 14 nm and a temporal resolution of approximately 50 ps. smFLIM enabled us to image, at the single molecule level, the Local Density of Optical States (LDOS, which is related to the inverse of the fluorescence lifetime) of dielectric nanoantennas and periodic arrays of hollow truncated plasmonic nanocones.
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