nanoantennas to image single molecules?

from the better-viewing-through-plasmons dept.
Gina Miller writes "A Purdue University press release 'Nanoantennas' could bring sensitive detectors, optical circuits describes mathematical simulations published by Purdue researchers that demonstrate that antennas made from metal wires and spheres only about 10 nm wide should be able to bend light in the opposite direction to the usual case to produce a 'super lens' that 'drastically improves the quality of medical diagnostic images.'"

The researchers showed how properly arranged nanowires could produce a 'negative index of refraction' by causing clouds of electrons, called plasmons, to move in unison. The plasmons should make possible manipulating light to simulate how electrons are manipulated in electronic circuits. Thus it should be possible to make computers that use photons to move signals.

The 'plasmonic' nanomaterials should also allow focusing light into areas much smaller than the wavelength of the light, thus producing sensors that 'might be able to detect even a single molecule of a substance.'

The original research was published in the March issue of the Journal of Nonlinear Optical Physics and Materials

Plasmon Modes in Metal Nanowires and Left-Handed Materials

Viktor A. Podolskiy, Andrey K. Sarychev and Vladimir M. Shalaev

The electromagnetic field distribution for thin metal nanowires is found, by using the discrete dipole approximation. The plasmon polariton modes in wires are numerically simulated. These modes are found to be dependent on the incident light wavelength and direction of propagation. The existence of localized plasmon modes and strong local field enhancement in percolation nanowire composites is demonstrated. Novel left-handed materials in the near-infrared and visible are proposed based on nanowire composites.

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