Institute of Optics, Information and Photonics, Erlangen Graduate School in Advanced Optical Technologies, Friedrich-Alexander-University Erlangen-Nuremberg (FAU) and Max Planck Institute for the Science of Light , 91058 Erlangen, Germany.
Nano Lett. 2013 Sep 11;13(9):4539-45. doi: 10.1021/nl402580c. Epub 2013 Aug 23.
We experimentally demonstrate plasmonic nanocircuits operating as subdiffraction directional couplers optically excited with high efficiency from free-space using optical Yagi-Uda style antennas at λ0 = 1550 nm. The optical Yagi-Uda style antennas are designed to feed channel plasmon waveguides with high efficiency (45% in coupling, 60% total emission), narrow angular directivity (<40°), and low insertion loss. SPP channel waveguides exhibit propagation lengths as large as 34 μm with adiabatically tuned confinement and are integrated with ultracompact (5 × 10 μm(2)), highly dispersive directional couplers, which enable 30 dB discrimination over Δλ = 200 nm with only 0.3 dB device loss.
我们通过使用工作在 1550nm 波长的光学 Yagi-Uda 天线的高效自由空间激发，实验演示了作为亚波长定向耦合器的等离子体纳米电路。光学 Yagi-Uda 天线设计用于高效率（耦合 45%，总发射 60%）、窄角定向性（<40°）和低插入损耗地馈送通道等离子体波导。表面等离激元（SPP）通道波导表现出长达 34μm 的传播长度，具有渐变约束的特点，并与超紧凑（5×10μm2）、高色散的定向耦合器集成，仅通过 0.3dB 的器件损耗即可实现 30dB 的Δλ=200nm 的分辨。
