We present a polarization-insensitive plasmonic photoconductive terahertz emitter that uses a two-dimensional array of nanoscale cross-shaped apertures as the plasmonic contact electrodes. The geometry of the cross-shaped apertures is set to maximize optical pump absorption in close proximity to the contact electrodes. The two-dimensional symmetry of the cross-shaped apertures offers a polarization-insensitive interaction between the plasmonic contact electrodes and optical pump beam. We experimentally demonstrate a polarization-insensitive terahertz radiation from the presented emitter in response to a femtosecond optical pump beam and similar terahertz radiation powers compared to previously demonstrated polarization-sensitive photoconductive emitters with plasmonic contact electrode gratings at the optimum optical pump polarization.
|Original language||English (US)|
|State||Published - Nov 16 2017|
Bibliographical noteKAUST Repository Item: Exported on 2020-10-01
Acknowledgements: The authors gratefully acknowledge the financial support from Moore Inventor Fellowship, National Institutes of Health (#1R01GM112693-01A1), and King Abdullah University of Science and Technology Competitive Research Grant.
This publication acknowledges KAUST support, but has no KAUST affiliated authors.