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arXiv · 1202.2521

Actively tunable optical Yagi-Uda nanoantenna with bistable emission characteristics

Ivan S. Maksymov·Andrey E. Miroshnichenko·Yuri S. Kivshar
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Abstract

We suggest and study theoretically a novel type of optical Yagi-Uda nanoantennas tunable via variation of the free-carrier density of a semiconductor disk placed in a gap of a metallic dipole feeding element. Unlike its narrowband all-metal counterparts, this nanoantenna exhibits a broadband unidirectional emission and demonstrates a bistable response in a preferential direction of the far-field zone, which opens up unique possibilities for ultrafast control of subwavelength light not attainable with dipole or bowtie architectures.

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Ivan S. Maksymov, Andrey E. Miroshnichenko, Yuri S. Kivshar. 2012-02-12. Actively tunable optical Yagi-Uda nanoantenna with bistable emission characteristics. https://arxiv.org/abs/1202.2521

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