Coupling model for an extended-range plasmonic optical transformer scanning probe

The expansion of nanoscale optics has generated a variety of scanning probe geometries that yield spatial resolution below 10 nm. In this work, we present a physical model for coupling far-field radiation to plasmonic modes on the surface of a scanning probe, and propose a scheme for extending the working distance of such a probe. In a subsurface application, an optical transformer at the tip of a probe can be coupled to a remote near-field antenna placed inside the sample at a distance away from the surface, expanding the effective working distance up to 100 nm. © 2014 CIOMP. All rights reserved 2047-7538/14.