Embedded plasmonic waveguides with Yagi-style antennas

High confinement in plasmonic waveguides usually comes along with high loss. We present experiments on a new approach, which allows to tune adiabatically between high confinement and low loss waveguides, connected to optical Yagi-style antennas

Functional plasmonic nanocircuits with low insertion and propagation losses

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 λ_0 = 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

Experimental cross-polarization detection of coupling far-field light to highly confined plasmonic gap modes via nanoantennas

We experimentally demonstrate the coupling of far-field light to highly confined plasmonic gap modes via connected nanoantennas. The excitation of plasmonic gap modes is shown to depend on the polarization, position and wavelength of the incident beam. Far-field measurements performed in crossed polarization allow for the detection of extremely weak signals re-emitted from gap waveguides and can increase the signal-to-noise ratio dramatically.Comment: 5 figures; http://apl.aip.org

Negative refraction due to discrete plasmon diffraction

We experimentally demonstrate spectrally broad (λ_0=1200-1800 nm) in-plane negative diffraction of SPPs in an array of plasmonic channel waveguides with negative mutual coupling resulting in negative refraction on the array's interface and refocusing in an adjacent metal layer

Efficient Excitation of Channel Plasmons in Tailored, UV-Lithography-Defined V-Grooves

[Image: see text] We demonstrate the highly efficient (>50%) conversion of freely propagating light to channel plasmon-polaritons (CPPs) in gold V-groove waveguides using compact 1.6 μm long waveguide-termination coupling mirrors. Our straightforward fabrication process, involving UV-lithography and crystallographic silicon etching, forms the coupling mirrors innately and ensures exceptional-quality, wafer-scale device production. We tailor the V-shaped profiles by thermal silicon oxidation in order to shift initially wedge-located modes downward into the V-grooves, resulting in well-confined CPPs suitable for nanophotonic applications

Subwavelength plasmonic directional couplers for nonlinear switching and wavelength division

Plasmonic gap waveguides allow for subwavelength integration of optical circuitry. A side effect is extraordinarily high field enhancement. Here we present experimental and numeric results, which indicate nonlinear switching in a directional coupler. (C) 2011 Optical Society of Americ

Plasmonic nanocircuitry with embedded subwavelength waveguides and Yagi-style antennas

High confinement in plasmonic waveguides usually comes along with high loss. We present experiments on a new approach, which allows to tune adiabatically between high confinement and low loss waveguides, connected to optical Yagi-style antennas. (c) 2008 Optical Society of Americ