:: from silicon to plastic based computers
Flexible displays, inexpensive solar cell, computers that store more data in less space, process data faster, and consume less power, even computers that boot up instantly. That's the horizon of spintronics, a new kind of electronics that employs not only the charge but also the spin of electrons in making electrical devices. Spintronics uses magnetic fields to control the spin of electrons.
Scientists from Ohio State's Center for Materials Research used a magnetic field to make nearly all the moving electrons inside a sample of plastic spin in the same direction, an effect called spin polarization. The achievement of spin polarization in a polymer is the first step in converting the plastic into a device that could read and write spintronic data inside a working computer.
Normal electronics encode computer data based on a binary code of ones and zeros, depending on whether an electron is present in a void within the material. But in principle, the direction of a spinning electron -- either 'spin up' or 'spin down' -- can be used as data, too. So spintronics would effectively let computers store and transfer twice as much data per electron.
Once a magnetic field pushes an electron into a direction of spin, it will keep spinning the same way until another magnetic field causes the spin to change. This effect can be used to very quickly access magnetically stored information during computer operation -- even if the electrical power to a computer is switched off between uses. Data can be stored permanently, and is nearly instantly available anytime, no lengthy boot up needed.
Plastic spintronics would weigh less than traditional electronics and cost less to manufacture. Today's inorganic semiconductors are created through multiple steps of vacuum deposition and etching. Theoretically, inexpensive ink-jet technology could one day be used to quickly print entire sheets of plastic semiconductors for spintronics. >from Plastic Shows Promise For Spintronics, Magnetic Computer Memory. September 25, 2002.
> spintronics: one terabit per square inch data storage. june 26, 2002
> magnetic semiconductor: spintronics advance. november 13, 2001