title: Aperture scanning near-field optical microscopy and spectroscopy of single terrylene molecules at 1.8 K.
abstract: Single-molecule imaging and spectroscopy using an aperture scanning near-field optical microscope operating at 1.8 K in a helium bath cryostat is demonstrated. From near-field images at constant excitation frequency, the orientation of single molecules can be deduced. Spectral information is obtained using both near-field and confocal excitation schemes by scanning the excitation frequency at a fixed sample position. Differences between near-field and confocal spectra are discussed in terms of the position with respect to the aperture and the molecular orientation.
authors.affiliation: Nano-Optics group, National Center of Competence for Research in Nanoscale Science, Institute of Physics, University of Basel, Klingelbergstrasse 82, CH-4056 Basel, Switzerland.
authors.forename: J Y P
authors.initials: JY
authors.lastname: Butter
authors.forename: B
authors.initials: B
authors.lastname: Hecht