Fusion, the reaction that produces the sun’s energy, is thought to have enormous potential for future power generation because fusion plant operation produces no emissions, fuel sources are potentially abundant, and it produces relatively little (and short-lived) radioactive waste. But it still faces great hurdles.

“There’s been a lot of progress,” says physicist Earl Marmar, division head of the Alcator Project at the MIT Plasma Science and Fusion Center (PSFC). “We’re learning a lot more about the details of how these things work.”

The Alcator C-Mod reactor, in operation since 1993, has the highest magnetic field and the highest plasma pressure of any fusion reactor in the world, and is the largest fusion reactor operated by any university.

One of the most vexing issues facing those trying to construct a fusion plant that produces more power than it consumes (something never achieved yet experimentally) is how to propel the hot plasma (an electrically charged gas) around inside the donut-shaped reactor chamber. This is necessary to keep it from losing its heat of millions of degrees to the cooler vessel walls. Now, the MIT scientists think they may have found a way.


http://www.physorg.com/news147528679.html

Researchers have solved one of the significant remaining challenges with photonic “metamaterials,” discovering a way to prevent the loss of light as it passes through these materials, and opening the door to many important new optical, electronic and communication technologies.

The advance, made by scientists from Oregon State University and Norfolk State University, was just published in Physical Review Letters.

“The ability to compensate for optical loss is a very large step forward for the whole field of active plasmonics,” said Viktor Podolskiy, an OSU assistant professor of physics. “Some of the most important potential applications in this field have been held back by this problem.”

These “metamaterials,” which gain their properties from their structure rather than directly from their composition, have been seen as a key to a possible “super lens” that would have an extraordinary level of resolution and be able to “see” things the size of a nanometer – a human hair is 100,000 nanometers wide.

They could also be important in machine visions systems, electronics manufacturing, computers limited only by the speed of light, and a range of new communications concepts. A “cloaking device” to hide objects, although not exactly of the type made famous by Star Trek, is also a possibility.


http://www.physorg.com/news147542890.html