Aperture scanning near-field optical microscopy and spectroscopy of single terrylene molecules at 1.8 K

Nanotechnology. 2006 Mar 28;17(6):1547-50. doi: 10.1088/0957-4484/17/6/002. Epub 2006 Feb 21.

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.