All-Optical Switching and Unidirectional Plasmon Launching with Nonlinear Dielectric Nanoantennas
| Autor: | Denis G. Baranov, Alex Krasnok, Roman S. Savelev, Andrea Alù, Sergey Lepeshov, Sergey V. Li |
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| Rok vydání: | 2018 |
| Předmět: |
Permittivity
Materials science business.industry Van Hove singularity Nanophotonics Physics::Optics General Physics and Astronomy 02 engineering and technology Dielectric Laser pumping 021001 nanoscience & nanotechnology 01 natural sciences Photoexcitation 0103 physical sciences Polariton Optoelectronics 010306 general physics 0210 nano-technology business Plasmon |
| Zdroj: | Physical Review Applied. 9 |
| ISSN: | 2331-7019 |
| DOI: | 10.1103/physrevapplied.9.014015 |
| Popis: | High-index dielectric nanoparticles have become a powerful platform for nonlinear nanophotonics due to special types of optical nonlinearity, e.g. caused by electron-hole plasma (EHP) photoexcitation. We propose a highly tunable dielectric nanoantenna consisting of a chain of silicon particles excited by a dipole emitter. The nanoantenna exhibits slow group-velocity guided modes, corresponding to the Van Hove singularity in an infinite structure, which enable a large Purcell factor up to several hundred and are very sensitive to the nanoparticle permittivity. This sensitivity enables the nanoantenna tuning via EHP excitation with an ultrafast laser pumping. Dramatic variations in the nanoantenna radiation patterns and Purcell factor caused by ultrafast laser pumping of several boundary nanoparticles with relatively low intensities of about 25 GW/cm2 are shown. Unidirectional surface-plasmon polaritons launching with EHP excitation in the nanoantenna on a Ag substrate is demonstrated. |
| Databáze: | OpenAIRE |
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