Free-field characterization via directional transmission through a nanoaperture
1 Department of Physics and Mathematics, University of Eastern Finland, P.O. Box 111, Joensuu FI-80101, Finland
2 Rocsole Ltd, Microkatu 1, P.O. Box 1188, Kuopio FI-70211, Finland
3 Department of Bioengineering, National University of Singapore, 7 Engineering Drive 1, Singapore 117574, Singapore
4 Singapore-MIT Alliance for Research and Technology, 3 Science Drive 2, Singapore 117543, Singapore
Nanoscale Research Letters 2013, 8:326 doi:10.1186/1556-276X-8-326Published: 16 July 2013
We propose a scheme based on extraordinary transmission of light through a single nanoaperture, surrounded by periodic corrugations, for direct characterization of focal-region optical fields with subwavelength-scale structure. We describe the design of the device on the basis of rigorous diffraction theory and fabricate a prototype using a process that involves electron beam lithography, dry etching, and template stripping. First experimental results performed with a transmission-type confocal optical microscope demonstrate the potential of the method.