Correlative imaging in scanning near-field optical microscopy

Abstract

Operational aspects of a newly developed simultaneous near-field optical and force microscope are considered. Using a glass probe, the technique is capable of monitoring the sample topography, through its force microscopy capability, as well as the sample’s optical parameters, using the light guiding properties of the tip. In addition, the force signal can be used reliably as a feedback signal, thus allowing a crash-free detection of optical fields in the vicinity of opaque steps on the sample. Results are presented on imaging a variety of samples including biological and nonbiological objects and thin film structures. In each instance, results obtained with different modalities are compared. It is shown that the simultaneity of the images obtained with different modalities can be very useful in, and sometimes necessary for, sample identification.