H F. Hamann, M Larbadi, S Barzen, T Brown, Alan Gallagher, David Nesbitt
Two AFM-assisted, apertureless, optical-imaging methods are presented. These overcome the severe resolution consrtaints of aperture-based Near-field Scanning Optical Microscopy by probing the highly localized mutual near-field interaction between AFM-tip and sample. Specifically, we monitor the evanescent field scattering and the extinction of the reflected intensity while the tip is scanned over Au-nanoparticles. We describe a significant improvement in optically detected spatial resolution (approximately equal to} 2 nm to 3 nm) and introduce a new, more quantitative method for optical imaging.