Spin waves could unlock the next generation of computer technology. A new component allows physicists to control them.
Aalto University researchers have created a new spintronics device. These results were published in the Nature Communications journal and represent a step toward the goal of spinning to develop small- and powerful computer chips and devices that process data.
Traditional electronics use an electrical charge to perform computations that power most modern technology. Engineers can’t make electronics perform calculations faster because moving control creates heat. We are at the limit of how small and quick chips can be before they overheat. Electronics can’t get smaller, so there are fears that computers will become less potent or cheaper like they have for the past seven decades. This is where spintronics steps in.
“Spin” can be described as a property of particles, such as electrons, in the same manner, that “charge” is. Because it doesn’t heat up like current computer chips, spin is a popular method of computing. “If you use Spin Waves, it’s the transfer of spin, you don’t move charge, so you don’t create heating,” Professor Sebastiaan Van Dijken, the research group leader that created the paper, says.
Nanoscale magnetic materials
The Fabry-Perot resonator is a well-known tool in optics that creates beams of light with a controlled wavelength. Researchers created a spin-wave version of the device to filter spin waves in machines with a small size (a few hundred nanometers).
These devices were created by sandwiching thin layers of exotic magnetic materials on top of one another. The device would trap spin waves within the material and cancel them out if they aren’t at the desired frequency. The concept is novel but easy to implement,” says Dr. Huajun Qin. “The trick is to make high-quality materials, which we have at Aalto.” These devices are easy to make, so there is plenty of opportunity for exciting new work.
Analog computing and wireless data processing
Overheating can cause problems with electronics. Wireless transmissions are also affected by them. Wireless signals must be converted from higher frequencies to frequencies that electronic circuits will handle. This slows down the process and consumes energy. Spin wave chips can operate at microwave frequencies used in mobile phones and wifi signals. This means there is great potential to use them in wireless communication technologies that are faster and more reliable in the future.
Spin waves can also perform computing faster than electronic computing for specific tasks. “Electronic computing uses Boolean and Binary logic to do calculations,” explained Professor van Dijken. “With spin waves, the information in the amplitude is carried, which allows more analog-style computing.” This makes it useful for specific tasks like pattern recognition or image processing. Our system’s size means it can be easily integrated into existing technology.
The team now has a resonator that can filter and control spin waves. Now it is time to build a complete circuit. To construct a magnetic circuit, we must be able to guide spin waves to functional components. This is similar to how conducting electrical channels work on microchips. Dr. Qin explains that similar structures are being considered to steer spin waves.