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Milyen lehetőségek rejlenek a nanoszintű plazmonika technológiában?

A team of European researchers has demonstrated some of the first commercially viable plasmonic devices, paving the way for a new era of high-speed communications and computing in which electronic and optical signals can be handled simultaneously. The pioneering devices, which are expected to lead to commercial applications within the next decade, make use of electron plasma oscillation to transmit optical and electronic signals along the same metal circuitry via waves of surface plasmon polaritons. In contrast, signals in electronic circuits are transmitted by electrons, while photons are used to carry data in optical systems. As an emerging nano-scale technology that is often referred to as “light on a wire,” plasmonics, as the field of research is known, shares the advantages of fibre optics, including ultra-high-speed data transfer, with the benefits of electronic components, particularly their small size. The technology holds the promise of all-optical computer chips operating at ultra-fast speeds, faster communications and a vast new range of sensing devices. “For the last five years or so it has been possible to build an optical computer chip, but with all-optical components it would have to measure something like half a metre by half a metre and would consume enormous power. With plasmonics, we can make the circuitry small enough to fit in a normal PC while maintaining optical speeds,” explains Anatoly Zayats, a researcher at The Queen's University of Belfast. Until now, however, plasmonic devices had been let down by the short distance over which plasmons could transmit data signals – a problem that Zayats and his team solved in the EU-funded Plasmocom project. Plasmonic data transmission functions on the basis of oscillations in the electron density at the boundary of two materials: a dielectic (non-conductive) plasma or polymer and a metal surface. By exciting the electrons with light it is possible to propagate high-frequency waves of plasmons along a metal wire or waveguide, thus transmitting a data signal. However, in many cases the signal dissipates after only a few micrometres – far too short to interconnect two computer chips, for example.The Plasmocom team took a novel approach. The researchers built a variety of plasmonic devices, including low-loss S bends, Y-splitters and a waveguide ring resonator, a crucial part of the add-drop multiplexers (ADM) in optical networks that combine and separate several streams of data into a single signal and vice versa. While current commercial optical ring resonators have a radius of up to 300 micrometres, the plasmonic demonstrator built by the Plasmocom team measured just five micrometres.

IT3 komment: A fotonika és elektronika előnyeit egyaránt ötvőző műszaki megoládsokkal kecsegtet csipgyártás területén a plazmonika. A plazmonika fő ígérete a THz-es sebességű optikai processzor nanométeres tartományban. A kutatási eredmények azt mutaják, hogy 10 éven belül lehetővé válik a "plazmoprocesszorok" létrehozása.

Forrás: cordis.europa.eu