We demonstrate the design, fabrication and characterization of a near-field plasmonic nanofocusing probe with a hybrid tip-plus-aperture design. By combining template stripping with focused ion beam lithography, a variety of aperture-based near-field probes can be fabricated with high optical performance. In particular, the combination of large transmission through a C-shaped aperture aligned to the sharp apex (<10 nm radius) of a template-stripped metallic pyramid allows the efficient delivery of light - via the C-shaped aperture - while providing a nanometric hotspot determined by the sharpness of the tip itself.
Bibliographical noteFunding Information:
This work was supported by the Office of Naval Research (ONR) Young Investigator Award (N00014-11-1-0645) and the National Science Foundation CAREER Award (DBI 1054191). N.C.L. was supported with a University of Minnesota Doctoral Dissertation Fellowship. T.W.J. was supported with a NIH Biotechnology Trainee Fellowship. We also utilized resources at the University of Minnesota, including the Nanofabrication Center, which receives partial support from NSF through the National Nanotechnology Infrastructure Network (NNIN), and the Characterization Facility, which has received capital equipment funding from NSF through the MRSEC program. Finally, the authors wish to thank Seagate Technology for partial financial support through the U. of Minnesota Center for Micromagnetics and Information Technologies (MINT).