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A fast-growing body of nanotechnology research is dedicated to nanoscale motors and molecular machinery. The results of these studies are spectacular: well-designed molecules or supramolecules show various movements upon exposure to various stimuli, such as molecular shuttles, molecular elevators and molecular motors.

So far, however, nobody has been able to directly observe the movements of these molecular machines and utilize the mechanical work done by them. Now, an international group of researchers have succeeded in amplifying the minuscule change in structures at a molecular level caused by an external stimulus (light) to a macroscopic change through a cooperative effect of liquid crystals.

Using liquid-crystalline elastomers (LCEs) – unique materials having both properties of liquid crystals (LCs) and elastomers – the scientists have successfully developed new photomechanical devices, including the first light-driven plastic motor.

Source: http://www.nanowerk.com/spotlight/spotid=6122.php

Engineers and applied physicists from Harvard University have demonstrated the first room-temperature electrically-pumped semiconductor source of coherent Terahertz (THz) radiation, also known as T-rays. The breakthrough in laser technology, based upon commercially available nanotechnology, has the potential to become a standard Terahertz source to support applications ranging from security screening to chemical sensing.

Spearheaded by research associate Mikhail Belkin and Federico Capasso, Robert L. Wallace Professor of Applied Physics and Vinton Hayes Senior Research Fellow in Electrical Engineering, both of Harvard's School of Engineering and Applied Sciences (SEAS), the findings were published in the May 19 issue of Applied Physics Letters. The researchers have also filed for U.S. patents covering the novel device.

Source: http://www.eurekalert.org/pub_releases/2008-05/hu-edf051508.php

A simple technique can draw--and erase--wires to create denser computer memory.

It may be the world's tiniest Etch-a-Sketch. Researchers have demonstrated a new technique that could be used to create rewritable logic circuits and denser computer memory. Using an atomic force microscope (AFM), the researchers were able to draw nano-sized wires and dots that could be repeatedly erased and written.

Led by Jeremy Levy of the University of Pittsburgh, the researchers used an AFM tip like a pencil, drawing electrically conductive paths--which act like metallic wires--on a special material. The lines were as thin as three nanometers, making them considerably narrower than the lines that can be drawn using electron beam lithography--one of the most precise techniques for etching devices out of silicon.

Source: http://www.technologyreview.com/Nanotech/20362/

A team of electrical engineers from Stanford University and Toshiba have developed nanotube wires that can withstand data transfer speeds comparable to those of commercially available chips. In a paper published in the “Nano Letters” Journal, the researchers reported they had successfully used nanotubes to wire a silicon chip operating at the same speeds as today’s processors. The technology developed by the team may enable the continuation of Moore’s Law for years to come, doubling the number of transistors on a chip every two years.

As copper conduits in silicon chips are fast approaching their physical limitations, many have suggested using carbon nanotubes to create thinner wiring that will be compatible with modern chips. Thinner wiring will allow packing an even larger amount of transistors on a given surface. However, until today, no chipmaker was able to demonstrate nanotube wires that worked on a conventional silicon chip. "This is the first time anyone has been able to show digital signals going through nanotubes at 1 gigahertz”, said Philip Wong, Professor of Electrical Engineering at Stanford University and a co-author of the paper. "There had been a lot of expectations that nanotubes could do this, but no experimental proof so far."

Source: http://www.tfot.info/news/1106/high-speed-carbon-nanotube-based-chips.html

The ability to create flexible, transparent electronics could lead to a host of novel applications, such as e-paper and electronic car windshields. Now, scientists have constructed a transistor made of a network of nanotubes that may serve as an essential component in a trans-flex device.

Such devices require two main components: light displays and current-controlling transistors. While scientists have found that OLEDs and LCDs work well as light displays, finding a truly transparent and flexible transistor material is still an open area. Usually, these transistors consist of metallic nanowires.

Recently, researchers from Hanyang University in Seoul have constructed a thin film transistor made of networked single-walled carbon nanotubes (SWNTs) on a glass substrate. While it’s not the first thin film transistor made of SWNTs, it has the advantage of allowing a high density of SWNTs to be grown under lower temperatures than normally required.

Source: http://www.physorg.com/news115382102.html