Physicists have nudged electrons to change their spin in just quadrillionths of a second, the fastest ever achieved and a basic-science feat that could lead to faster computer processing and storage.
Electrons have three basic properties: mass, electric charge and spin. The spin is a form of angular momentum, which relates to how an electron moves around the nucleus of an atom. An electron's spin comes in two flavors: up and down.
Manipulating electrons is important for computing since most data storage these days is magnetic and relies on aligning the spin of electrons in a material. In recent years, a new technology known as spintronics has emerged that aims to control both the spin and the electric charge of electrons to improve how information is stored. The technology relies on the rapid switching of magnetic fields, which can now be done within quadrillionths of a second, a new study shows.
"We may expect faster writing in hard drives and faster reading and writing in [computer memory] with even less power used," said Jigang Wang, a physicist at Ames Laboratory in Iowa. The technology could someday be used, for example, to show extremely fast HD movies, Wang added.
Spintronics researchers have been faced with the hurdle of figuring out how to go from the gigahertz speed of today's conventional computer memory and logic systems to the terahertz speed. Doing so requires an understanding of what's happening during magnetic switching on very brief timescales.
The real achievement, though, was doing this about a thousand times faster than current technology. To visualize how the material changed its magnetic properties, the scientists used a special type of imaging to take snapshots of the process — similar to taking a photo under a strobe light. Using this technique, the researchers saw how the magnetization started developing during the laser pulses.
On these very short timescales, conventional thermodynamics is not important, and quantum mechanics takes over.more