Routing and photodetection in subwavelength plasmonic slot waveguides

Abstract

The ability to manipulate light at deeply sub-wavelength scales opens a broad range of research possibilities and practical applications. In this paper, we go beyond recent demonstrations of active photonic devices coupled to planar plasmonic waveguides and demonstrate a photodetector linked to a two conductor metallic slot waveguide that supports a mode with a minute cross-sectional area of ∼ λ 2 /100. We demonstrate propagation lengths of ∼ 10 λ (at 850 nm), routing around 90 ° bends and integrated detection with a metal-semiconductormetal (MSM) photodetector. We show polarization selective excitation of the slot mode and measure its propagation characteristics by studying the Fabry-Perot oscillations in the photo current spectra from the waveguide-coupled detector. Our results demonstrate the practicality of transferring one of the most successful microwave and RF waveguide technologies to the optical domain, opening up many opportunities in areas such as biosensing, information storage and communication.

Subwavelength Plasmonic Two‐Conductor Waveguides

“…The slot waveguide is formed by appropriate lithography and etch- ing techniques. Electron beam lithography (95,96,98) and focused ion beam lithography (37,95,97,99) are the most widely used techniques to create fine nanoscale features on the metallic layer ( Figure 19). These techniques can produce linewidths on the order of 10 nm or smaller.…”

“…However, these methods are slow because they pattern the sample serially, which makes them impractical as a mass production method in manufacturing of plasmonic devices. Dry argon/xenon ions remove the exposed areas after lithography (96)(97)(98). Nanoimprint lithography (NIL) represents a low-cost and high-throughput fabrication method.…”

Second harmonic generation using an electrically controlled asymmetric plasmonic waveguide

“…Therefore, the optical mode can be confined to the sub-wavelength scale, and the size of the optical mode can be minimised. For example, light can be confined to a size 100 times smaller than its CONTACT Mohamadreza Soltani mrsoltani@iautiran.ac.ir wavelength [3,4,[6][7][8]. This surface localisation makes plasmonic waveguides an intriguing alternative to conventional dielectric waveguides.…”

Magnetic plasmon induced transparency in three-dimensional metamolecules

“…These unique characteristics also enable us to explore tunability and nonlinearity that either do not exist in nature or are too weak for practical applications [11,12] . The magnetic and electric responses of artifi cial metamolecules play a similar role to those of atoms in electromagnetic media.…”