Low cross-talk, deep subwavelength plasmonic metal/insulator/metal waveguide intersections with broadband tunability
We suggest a low cross-talk plasmonic cross-connector based on a metal/insulator/metal cavity and waveguides. We separately investigate the isolated cavity mode, the waveguide mode, and the combination of cavity and waveguide modes using a finite-different time-domain method. Due to resonant tunneling and the cutoff frequency of the odd waveguide mode, our proposed structure achieves a high throughput transmission ratio and eliminates cross-talk. Furthermore, the proposed structure has a broadband tunability of 587 nm, which can be achieved by modulating the cavity air gap thickness. This structure enables the miniaturization of photonic integrated circuits and sensing applications.
基金项目：National Research Foundation of Korea (NRF) (NRF-2015R1A2A1A15055998, NRF-2013M3C1A3065051, NRF-2016R1C1B2007007).
Da Eun Lee：Department of Physics, Chung-Ang University, Seoul 06974, South Korea
Young Jin Lee：Department of Physics, Chung-Ang University, Seoul 06974, South Korea
Soon-Hong Kwon：Department of Physics, Chung-Ang University, Seoul 06974, South Korea
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Tae-Woo Lee, Da Eun Lee, Young Jin Lee, and Soon-Hong Kwon, "Low cross-talk, deep subwavelength plasmonic metal/insulator/metal waveguide intersections with broadband tunability," Photonics Research 4(6), 272-276 (2016)