Electrons are elementary particles whose motion along conductors is the basis of electronics. As is well known, besides mass and electric charge they have one more physical parameter, spin.
Spin (from the English spin, to rotate) is a form of magnetic angular momentum connected with the motion of an electron around the atomic nucleus and is quantum in nature. The spin of an electron exists in two states: spin up, whose vector coincides with the magnetisation vector of the magnetic material, and spin down, where the spin and the magnetisation point in different directions.
Because the mechanism of the overwhelming majority of electronic information carriers today is based on the use of magnetic fields, the processing and manipulation of electrons is of enormous importance for logic systems.
At the beginning of the 21st century a new field of quantum electronics took shape, spin electronics or spintronics, whose aim is to control the spin and the charge of electrons in order to modernise the ways in which information is stored. Where generally accepted electronics uses the movement of electric charges, in spintronics the key physical principle is the movement of the spins of electrons.
The latest innovative research has made it possible, by switching magnetic fields sharply, to change the spins of electrons in one quadrillionth of a second, which is an enormous step for the electronics of the new generation.
Jigang Wang, the lead author of the research and a physicist at the Ames Laboratory, believes that such a breakthrough in spintronics will make it possible in the near future to create electronic data carriers with an inconceivably fast rate of information processing, and with the use of far less electrical energy at that.
Scientists are continuing to develop new solutions to the problem of moving from the standard gigahertz speed of computer memory to the terahertz one.
There is a need to understand what happens at the moment of magnetic switching.
Answering this question, the researchers illuminated an unusual magnetic material with an ultrashort laser pulse, which nudged and excited the atoms and changed their properties.
The real success of this research, however, is reaching a speed tens of thousands of times greater than the one used in present-day technologies.
Wang and his colleagues state that generally accepted thermodynamics plays no substantial role over such a small time range during the switching of the fields, losing out in this to quantum mechanics.
The scientists say that a long time will pass before such a technology is used on a mass scale in commercial computers, but they are confident that in the near future it will be able to become available to everyone.