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For decades, the transistors inside radios, televisions and other everyday electronic items have transmitted data by controlling the movement of the charge of an electron. Scientists have since discovered that transistors that function by controlling an electron’s spin instead of its charge would use less energy, generate less heat and operate at higher speeds. This has resulted in a new field of research — spin electronics or spintronics — that offers one of the most promising paradigms for the development of novel devices for use in the post-CMOS (complementary metal–oxide–semiconductor) era.

"Until now, scientists have attempted to develop spin transistors by incorporating local ferromagnets into device architectures. This results in significant design complexities, especially in view of the rising demand for smaller and smaller transistors," says Philippe Debray, research professor in the Department of Physics in the McMicken College of Arts & Sciences. "A far better and practical way to manipulate the orientation of an electron’s spin would be by using purely electrical means, like the switching on and off of an electrical voltage. This will be spintronics without ferromagnetism or all-electric spintronics, the holy grail of semiconductor spintronics."

Source: http://www.uc.edu/news/NR.aspx?id=10872

Recently, at Arizona State University's Biodesign Institute, N.J. Tao and collaborators have found a way to make a key electronic component on a phenomenally tiny scale. Their single-molecule diode is described in this week's online edition of Nature Chemistry.

In the electronics world, diodes are a versatile and ubiquitous component. Appearing in many shapes and sizes, they are used in an endless array of devices and are essential ingredients for the semiconductor industry. Making components including diodes smaller, cheaper, faster and more efficient has been the holy grail of an exploding electronics field, now probing the nanoscale realm.

Smaller size means cheaper cost and better performance for electronic devices. The first generation computer CPU used a few thousand transistors, Tao says noting the steep advance of silicon technology. "Now even simple, cheap computers use millions of transistors on a single chip."

Source: http://www.sciencedaily.com/releases/2009/10/091013110042.htm

The physicists at UC San Diego that a year ago created the first integrated circuit using particles called excitons, now have discovered a technique that allows for operation at commercially cold temperatures.

This brings the possibility of a new type of extremely fast computer based on excitons closer to reality. When commercialized, the technology could speed computing and communications by better integrating electronic circuits and optical data communications.

Leonid Butov, a professor of physics at UCSD, is leading the research team that previously demonstrated an integrated circuit capable of working at 1.5 degrees Kelvin above absolute zero, or minus 457 degrees Fahrenheit. That temperature is less than the average temperature of deep space (-454.67 F), and achievable only in special research laboratories.

But now, the scientists report that they succeeded in building an integrated circuit that operates at 125 degrees Kelvin (minus 234 degrees Fahrenheit), a temperature that can be “easily” attained commercially with liquid nitrogen, a substance that costs about as much per liter as gasoline. The discovery is detailed in the latest online issue of the journal Nature Photonics.

Source: http://blogs.zdnet.com/emergingtech/?p=1793

Gaze into the electron microscope display in Frances Ross’s laboratory here and it is possible to persuade yourself that Dr. Ross, a 21st-century materials scientist, is actually a farmer in some Lilliputian silicon world.

Dr. Ross, an I.B.M. researcher, is growing a crop of mushroom-shaped silicon nanowires that may one day become a basic building block for a new kind of electronics. Nanowires are just one example, although one of the most promising, of a transformation now taking place in the material sciences as researchers push to create the next generation of switching devices smaller, faster and more powerful than today’s transistors.

The reason that many computer scientists are pursuing this goal is that the shrinking of the transistor has approached fundamental physical limits.

Source: http://www.nytimes.com/2009/09/01/science/01trans.html?_r=2&8dpc

A hybrid of silicon nanocircuits and biological components that mimics some of the processes that control the passage of molecules into and out of cells has been created by a team of scientists from UC Davis, Lawrence Livermore National Laboratory and UC Berkeley.

The lipid-coated nanocircuits could lead to the development of new classes of bio-sensing tools and biological applications, such as comprehensive blood-chemistry tests that fit on the point of a needle or screening tools for the development of new drugs.

“This is an example of a marriage between integrated circuit technology and biotechnology,” said Pieter Stroeve, a professor of chemical engineering and materials science at UC Davis and one of three lead scientists on the project. “The technology of both can be mass produced, so in theory, their integration can also be mass produced.”

Source: http://www.physorg.com/news170619218.html