Title Unidirectional Surface Plasmon-polariton Excitation by a Compact Slot Partially Filled with Dielectric Unidirectional Surface Plasmon-polariton Excitation by a Compact Slot Partially Filled with Dielectric References and Links

We propose a new scheme on unidirectional surface plasmonpolariton (SPP) excitation with the following advantages: ultracompact size, working at arbitrary incidence angle and over a wide spectrum. The proposed structure utilizes a partially filled metallic slot with dielectric to realize unidirectional SPP excitation via direct field manipulation. We theoretically and numerically show that unidirectional SPP excitation with a ratio of 93% can be achieved by a structure with a 50 nm slot. The proposed structure keeps its functional capability over incident angles from −80° to 80°, and has a broadband working spectrum of more than 70 nm. © 2013 Optical Society of America OCIS codes: (240.0240) Optics at surfaces; (240.6680) Surface plasmons. References and links 1. W. L. Barnes, A. Dereux, and T. W. Ebbesen, “Surface plasmon subwavelength optics,” Nature 424(6950), 824– 830 (2003). 2. S. A. Maier, Plasmonics: Fundamentals and applications (Springer, 2007), Chap. 2. 3. S. A. Maier, P. G. 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