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Since the 1980s, researchers have used lasers to stop molecular vibrations, so that the molecules can be observed in their natural environment. Now researchers at Yale University have used the same kind of nanoscale optical force to control an integrated circuit. Their device could form the basis of fast, low-power optical chips, just as transistors are the building blocks of today's electronic circuits. The new device, a light-driven nanoresonator, could also be used as an extremely sensitive chemical detector. The work is a major landmark in uniting mechanical and optical forces at the nanoscale.

Chips that use light instead of electrons to carry data should be faster and consume less power than traditional integrated circuits. But so far even the fastest optical chips have incorporated electrical elements called modulators. These modulators encode light with data by converting the signal from light into electrons and back again. This extra step makes optical chips complex and drains power. A circuit developed by Yale researchers led by electrical-engineering professor Hong Tang incorporates a modulator that's driven by light, not electrons.

Source: http://www.technologyreview.com/computing/21740/?a=f

Researchers at the University of California, Berkeley, have created nanoscale particles that can self-assemble into various optical devices. By controlling how densely the tiny silver particles assemble themselves, the researchers can make several different kinds of devices, including photonic crystals. The self-assembling materials could be made cheaply and on a large scale. As a result, the silver nanoparticles could be used to make metamaterials, color-changing paints, components for optical computers, and ultrasensitive chemical sensors, among many other potential applications.

Led by Peidong Yang, a professor of chemistry at Berkeley, the researchers have demonstrated that they can use the nanoparticles to increase the sensitivity of arsenic detection by an order of magnitude. They also made a very robust kind of photonic crystal called a plasmonic crystal. These new structures are "similar to photonic crystals, but better," says Peter Nordlander, a professor of physics at Rice University, who was not involved in the work. Photonic crystals allow some wavelengths of light to pass while filtering out others. They're used commercially to coat lenses and mirrors and in optical fibers; they could also be used in optical computers.

Source: http://www.technologyreview.com/computing/21636/?a=f

It's called "buckypaper" and looks a lot like ordinary carbon paper, but don't be fooled by the cute name or flimsy appearance. It could revolutionize the way everything from airplanes to TVs are made.

Buckypaper is 10 times lighter but potentially 500 times stronger than steel when sheets of it are stacked and pressed together to form a composite. Unlike conventional composite materials, though, it conducts electricity like copper or silicon and disperses heat like steel or brass.

That idea - that there is great future promise for buckypaper and other derivatives of the ultra-tiny cylinders known as carbon nanotubes - has been floated for years now. However, researchers at Florida State University say they have made important progress that may soon turn hype into reality.

Source: http://www.physorg.com/news143462841.html

Scientists at the University of Pennsylvania have theorized a way to increase the speed of pulses of light that bound across chains of tiny metal particles to well past the speed of light by altering the particle shape. Application of this theory would use nanosized metal chains as building blocks for novel optoelectronic and optical devices, which would operate at higher frequencies than conventional electronic circuits. Such devices could eventually find applications in the developing area of high-speed optical computing, in which protons and light replace electrons and transistors for greater performance.

Recent developments in nanotechnology have enabled researchers to fabricate nanoparticle chains with great precision and fidelity. Penn's research team took advantage of this technological advance by utilizing metallic nanoparticles as a chain of miniature waveguides that exchange light.

Currently, the advance is theoretical. But, from a practical standpoint, the creation of a metallic nanochain would provide the combination of smaller-diameter optical components coupled with larger bandwidth, making them optimal wave guiding materials.

Source: http://www.physorg.com/news138374177.html

Researchers at the University of California, Berkeley, have created the first integrated circuit that uses nanowires as both sensors and electronic components. With a simple printing technique, the group was able to fabricate large arrays of uniform circuits, which could serve as image sensors. "Our goal is to develop all-nanowire sensors" that could be used in a variety of applications, says Ali Javey, an electrical-engineering professor at UC Berkeley, who led the research.

Nanowires make good sensors because their small dimensions enhance their sensitivity. Nanowire-based light sensors, for example, can detect just a few photons. But to be useful in practical devices, the sensors have to be integrated with electronics that can amplify and process such small signals. This has been a problem, because the materials used for sensing and electronics cannot easily be assembled on the same surface. What's more, a reliable way of aligning the tiny nanowires that could be practical on a large scale has been hard to come by.

Source: http://www.technologyreview.com/Nanotech/21244/?a=f