May 2024

Researchers at the University of Wyoming, Pennsylvania State University, Northeastern University, The University of Texas at Austin, Colorado State University and Japan's National Institute for Materials Science have developed a method to control tiny magnetic states within ultrathin, two-dimensional van der Waals magnets - a process similar to how flipping a light switch controls a bulb.

The team developed a device known as a magnetic tunnel junction, which uses chromium triiodide - a 2D insulating magnet only a few atoms thick - sandwiched between two layers of graphene. By sending a tiny electric current called a tunneling current through this sandwich, the direction of the magnet's orientation of the magnetic domains (around 100 nanometers in size) can be dictated within the individual chromium triiodide layers.

Researchers at North Carolina State University, University of Pittsburgh, University of Illinois at Urbana-Champaign, Chinese Academy of Sciences and Beijing Normal University have studied how the spin information of an electron, called a pure spin current, moves through chiral materials. 

They found that the direction in which the spins are injected into chiral materials affects their ability to pass through them. These chiral “gateways” could be used to design energy-efficient spintronic devices for data storage, communication and computing.

An international team of researchers, led by scientists from the CNRS, has reported that the magnetic nanobubbles known as skyrmions can be moved by electrical currents, attaining record speeds up to 900 m/s.

Magnetic skyrmions are topological magnetic textures that hold great promise as nanoscale bits of information in memory and logic devices. While room-temperature ferromagnetic skyrmions and their current-induced manipulation have been demonstrated, their velocity has thus far been limited to about 100 meters per second, which is too slow for computing applications. In addition, their dynamics are perturbed by the skyrmion Hall effect, a motion transverse to the current direction caused by the skyrmion topological charge. 

Researchers from Tohoku University, University of Tokyo, Australian Nuclear Science and Technology Organization, High Energy Accelerator Research Organization and Comprehensive Research Organization for Science and Society have found that the spin current signal changes direction at a certain magnetic temperature and diminishes at lower temperatures.

Spintronics uses electrons’ intrinsic spin, which is vital to the field, to regulate the flow of the spin degree of freedom, that is, spin currents. Scientists are continually exploring new ways to manage spintronics for future uses. Detecting spin currents is quite complicated and necessitates the use of macroscopic voltage measurement, which examines the entire voltage fluctuations across a material. However, a major stumbling block has been a lack of understanding of how the spin current flows or propagates inside the material.