Plasmonic focusing on metal and semiconductor disks under radially polarized terahertz illumination
Plasmonic focusing on metal and semiconductor disks under radially polarized terahertz illumination
Kaltenecker, K. J.; Wallauer, J.; Waselikowski, S.; Hodapp, J.; Fischer, C.; Winnerl, S.; Schneider, H.; Fischer, B. M.; Walther, M.
Abstract
Optimal focusing of surface plasmon polaritons in the center of a metal disc illuminated by radially polarized terahertz pulses is demonstrated. Due to the cylinder symmetrical structure surface plasmons can be excited along the entire circumference, which interfere constructively in the center of the disk forming a sharp frequency-depended focal spot. We map the field distribution on the disk by THz near-field microscopy and compare our result to numerical simulations. For comparison, behavior under linearly polarized THz illumination is characterized. Furthermore, first results of semiconducting plasmonic lenses are presented.
Keywords: Terhertz radiation; plasmon polaritons; radial polarization
-
Lecture (Conference)
2013 38th International Conference on Infrared, Millimeter, and Terahertz Waves (IRMMW-THz 2013), 01.-06.09.2013, Mainz, Deutschland -
Contribution to proceedings
2013 38th International Conference on Infrared, Millimeter, and Terahertz Waves (IRMMW-THz 2013), 01.-06.09.2013, Mainz, Deutschland: IEEE Xplore Digital Library
DOI: 10.1109/IRMMW-THz.2013.6665612
Permalink: https://www.hzdr.de/publications/Publ-19664
