51. Hot electron generation by aluminum oligomers in plasmonic ultraviolet photodetectors
- Author
-
Phani Kiran Vabbina, Raju Sinha, Serkan Kaya, Arash Ahmadivand, Mustafa Karabiyik, and Nezih Pala
- Subjects
Photocurrent ,Materials science ,business.industry ,Photodetector ,Fano resonance ,Gallium nitride ,02 engineering and technology ,010402 general chemistry ,021001 nanoscience & nanotechnology ,medicine.disease_cause ,01 natural sciences ,7. Clean energy ,Atomic and Molecular Physics, and Optics ,0104 chemical sciences ,Responsivity ,chemistry.chemical_compound ,Optics ,chemistry ,medicine ,Optoelectronics ,Surface plasmon resonance ,0210 nano-technology ,business ,Plasmon ,Ultraviolet - Abstract
We report on an integrated plasmonic ultraviolet (UV) photodetector composed of aluminum Fano-resonant heptamer nanoantennas deposited on a Gallium Nitride (GaN) active layer which is grown on a sapphire substrate to generate significant photocurrent via formation of hot electrons by nanoclusters upon the decay of nonequilibrium plasmons. Using the plasmon hybridization theory and finite-difference time-domain (FDTD) method, it is shown that the generation of hot carriers by metallic clusters illuminated by UV beam leads to a large photocurrent. The induced Fano resonance (FR) minimum across the UV spectrum allows for noticeable enhancement in the absorption of optical power yielding a plasmonic UV photodetector with a high responsivity. It is also shown that varying the thickness of the oxide layer (Al2O3) around the nanodisks (tox) in a heptamer assembly adjusted the generated photocurrent and responsivity. The proposed plasmonic structure opens new horizons for designing and fabricating efficient opto-electronics devices with high gain and responsivity.
- Published
- 2016
- Full Text
- View/download PDF