Room temperature spintronics? New research hints at the holy grail
Room temperature spintronics is one of those things that, like military intelligence, has been impossible to arrange.
Spintronics is touted as the successor to electronics. The idea is that you control the state, or spin, of individual electrons, to encode information. This ultimately means that more devices can fit onto a single chip; the devices will out perform today's both in terms of processing speed and heat production.
However, controlling the spin of an electron is not a simple matter, especially when you add in all the messy heat of room temperature. Traditionally, close to absolute zero has been preferred. This is not so useful when you are trying to make computers for normal people.
But researchers at the University of Nebraska Lincoln now say they can manipulate the spin of electrons using simple voltage, and do it at room temperature.
From the press release:
The UNL MRSEC's team of scientists demonstrated a method that uses voltage to control electron spins at room temperature by growing a material that is easily magnetized on top of another exotic material called chromia.
The easily magnetized material, also called a "ferromagnetic film," carried the magnetization researchers wanted to use to electrically control the collective electron spin state. But since ferromagnets do not directly respond to electric fields, chromia--which produces excess magnetization when exposed to an electric field--was used to help transfer the influence of the electric field on the ferromagnetic film.
The UNL researchers controlled the collective spin state by applying a voltage with zero current to the chromia. They also were able to reverse the direction of all the spins in the ferromagnetic film. By doing this, they showed they could control electron spins in two distinct states, which is necessary to encode a "bit" of information, the basic unit of information in computing.
Information stored this way can be accessed immediately and processed with little to zero electric power consumption and vastly reduced heat.
The findings were published in Nature Materials. http://www.nanotech-now.com/news.cgi?story_id=39670