Field enhancement and apertureless near-field optical spectroscopy of single molecules

We report on fluorescence enhancement in near field optical spectroscopy by apertureless microscopy. Our apertureless microscope is designed around a confocal fluorescence microscope associated with an AFM head. First, we sho w that the confocal microscope alone allows single molecule imaging and sin gle molecule fluorescence analysis. When associated with the AFM head, we d emonstrate, for the first time to our knowledge, that single molecule fluor escence is enhanced under the silicon tip. We tentatively attribute this ef fect to field enhancement under the tip.