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Cornell's resonating ring waveguide device could be used to act as an optical filter or switch.  (Source: Cornell Nanophotonics Group)
New optical hardware may be powered by... light?

Beams of light are handy for illumination, from the size of a flashlight down to the fine scale of modern lasers. The meat and potatoes of a beam of light is the energy of which it is composed – oscillating electric and magnetic fields. And this energy can have a profound effect on objects near it. At least on a very, very small scale.

Though all light particles have force, you needn’t worry about dodging moonbeams at night. Even all the photons streaming to Earth during the day could never hope to budge something as small a hair, let alone a human body. On a much smaller level, though, where the wavelength of the light can be matched or represented in small multiples by microscopic devices, these effects can be realized and measured.

Researchers at Cornell University have managed to harness the sucking power of a beam of light to create what could be used as an optical switch or filter from two resonating rings and a small straight wave guide tuned to a frequency of infrared light. The rings themselves resemble four-spoke wheels, mounted like semi-tractor tires on one end of a rear axle. The silicon nitride rings have a diameter of 30 microns and are mounted 190 nanometers apart. The waveguide part of the ring, or the rubber part of our tractor tires, measures a scant 3 microns.

When light passes through a waveguide that is narrower than the wavelength of the light, some or most of the beam’s energy will escape the waveguide and this energy exerts an attractive force on objects near it. With this property in mind, the researchers mounted the resonating waveguides in close proximity so that their escaping energy would attract each other. By using this method, the group was able to expand or contract the distance between the waveguides by as much as 12 nanometers – enough to change the optical properties of the device creating what could be used as an optical switch or filter for other beams of light passed through the space.

This effect may also be useful in the field of micro-electromechanical systems, where forces at the subatomic and quantum levels, such as the Casimir force, create sticky situations for tiny mechanical parts. By reversing the phase of one of the resonating rings, the forces which once pulled the rings together instead push them apart. Controlled, this could help fight “stiction” as it has been dubbed.

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RE: Slight inaccuracy
By invidious on 11/18/2009 11:44:41 AM , Rating: 3
Light is absolutely a composed of electric and magnetic fields. You talk about light as if it is fundamentally different than other electromagnetic waves. This is simply untrue. The only difference between light waves and radio waves is wavelength and freuqnency.

Then you go on to compare speeds light to the speed electricity, but electricity refers to electron conduction. The difference in speed between the two has nothing to do with vacuums. Electon conduction is slowed down by collisions significantly (dependant on the conduction medium). And even if it wasn't, it would not travel as fast as light. Electron conduction speed and elecric field propogation speed are completely unrelated.

Perhaps you are just not using terms that accurately represent what you are trying to say. But I think you might want to read up a bit more on electromagnetics.

RE: Slight inaccuracy
By amanojaku on 11/18/2009 11:57:57 AM , Rating: 2
Electricity is NOT the flow of electrons through a conductor. If that was the case we would wait days and weeks for our power to reach us as electrically charged particles in our environment (Earth) generally move at walking speed or less.

While the particles themselves can move quite slowly, sometimes with an average drift velocity only fractions of a millimetre per second, the electric field that drives them itself propagates at close to the speed of light, enabling electrical signals to pass rapidly along wires.

Electricity is the propagation of the electric field, which is a byproduct of the electromagnetic field, and that field travels at the speed of light in a vacuum. Electrically charged particles can travel at high velocities, but that's dangerous for us and it is atypical to see such speeds in our atmosphere without colliders.

Please refer to my other post that addresses the rest of your comments with regards to light, electromagnetic waves, and electric and magnetic fields.

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