SPP Interference with MV4000 Two Probe System

The study of Surface Plasmon Polariton (SPP) interference and propagation is increasingly recognized as a very effective way to concentrate and guide light in nanometric domains. A team in the University of Science and Technology of China  demonstrated a unique approach for recording SPP interference from a "point" source on a plasmonic structure utilizing the Nanonics MultiView 4000^TM MultiProbe Scanning Probe Microscope (SPM) system.

MultiView 4000 Two Probe system setup has been used for NSOM excitation of SPPs with a point source of a 100nm and for NSOM collection of the interference patterns with a second NSOM probe with 100nm aperture.	NSOM images of the SPPs distribution on the sample with excitation position at b, c, d,  and e along the red line shown in a. d shows the numerical calculation

The researchers used two cantilevered 100nm aperture NSOM probes with the MultiView 4000 in order to test the relation between the visibility of interference patterns and the size of the point source. They observed the SPPs interference phenomenon of a ring structure with different point source sizes by using one probe as a point source for near-field excitation of SPPs and the other for near-field collection of the interference patterns

 The patterns were generated through the interference of the propagated and reflected SPPs to and from the ring walls. The intensity distribution of SPPs was measured in tip scanning mode with the sample and the illumination source kept stationary during the measurement.

Published: Appl. Phys. Lett. 98, 201113 (2011)