Plasmonic Density--The Exciting Opening of a Vast New Field of Science

Electromagnetic waves such as visible light, can generate electric energy through photovoltaics, can boost an electron to a higher energy level, and can create plasmons--density waves of electrons on a surface.

Plasmons are density waves of electrons, created when light hits the surface of a metal under precise circumstances. Because these density waves are generated at optical frequencies, very small and rapid waves, they can theoretically encode a lot of information, more than what's possible for conventional electronics. Source


Advanced Nano blog points to a SciAm article discussing the potential of plasmons to vastly increase data density on computer processor chips.

In the 1980s researchers experimentally confirmed that directing light waves at the interface between a metal and a dielectric (a nonconductive material such as air or glass) can, under the right circumstances, induce a resonant interaction between the waves and the mobile electrons at the surface of the metal. (In a conductive metal, the electrons are not strongly attached to individual atoms or molecules.) In other words, the oscillations of electrons at the surface match those of the electromagnetic field outside the metal. The result is the generation of surface plasmons--density waves of electrons that propagate along the interface like the ripples that spread across the surface of a pond after you throw a stone into the water.

....This phenomenon could allow the plasmons to travel along nanoscale wires called interconnects, carrying information from one part of a microprocessor to another. Plasmonic interconnects would be a great boon for chip designers, who have been able to develop ever smaller and faster transistors but have had a harder time building minute electronic circuits that can move data quickly across the chip.

....Ultimately it may be possible to employ plasmonic components in a wide variety of instruments, using them to improve the resolution of microscopes, the efficiency of light-emitting diodes (LEDs) and the sensitivity of chemical and biological detectors. Scientists are also considering medical applications, designing tiny particles that could use plasmon resonance absorption to kill cancerous tissues, for example. And some researchers have even theorized that certain plasmonic materials could alter the electromagnetic field around an object to such an extent that it would become invisible.

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