Researchers have made a breakthrough that could revolutionize computing by enabling the extreme miniaturization of components. The key lies in a new technique that utilizes ultrafast switching between spin states in 2D magnets, representing the binary states of 1 and 0. This allows for much denser and more power-efficient computing components.
The technique relies on a novel type of magnetic tunnel junction (MTJ), a structure that acts as a data storage device in computing systems. The scientists sandwiched chromium triiodide, a 2D insulating magnet, between layers of graphene and applied an electrical current to control the magnet’s orientation within the chromium triiodide layers. This breakthrough could enable packing more computing power into a chip than previously thought possible, while consuming significantly less energy during the switching process.
The research, published in the journal Nature Communications, highlights the potential of 2D magnets to represent binary states, paving the way for highly energy-efficient computing. The scientists demonstrated that precise control of the magnetic phase of 2D materials is crucial in spintronics, which involves manipulating an electron’s spin and associated magnetic moment.
By carefully adjusting the current’s polarity and amplitude, the new technique can change the spin states in chromium triiodide, utilizing its ferromagnetic and semiconducting properties. The compound’s ability to attract magnets and its conductivity between a metal and an insulator make it ideal for this application.
MTJs, comprising two ferromagnetic layers separated by an insulating barrier, are already used in various computer components, such as the read heads of hard drives. However, precisely controlling the thickness of these layers and their interfaces has been challenging. The new technique addresses this by using materials that can withstand high current densities while meeting the demands of device miniaturization and energy efficiency.
The researchers created 2D van der Waals (chromium triiodide) magnets, layering atomically thin flakes of graphene, hexagonal boron nitride, and chromium triiodide. These layers were chilled to near absolute zero, and an electrical current was passed through them while measuring voltage in 16-millisecond bursts. The voltage switched randomly between levels, representing the spin-parallel and spin-antiparallel states within chromium triiodide, with the switching direction determined by the current’s polarity and amplitude.
While the magnetic states are not entirely stable, they persist for a sufficient time, allowing for deterministic selection of two distinct states. These states can serve as logic gates, enabling operation at a smaller scale than previously possible. This breakthrough could lead to the creation of computer chips with greater processing power. However, the requirement for near absolute-zero operating temperatures poses a challenge for practical implementation.
The researchers emphasize that the energy required to transition between states in this new technique is significantly lower than in conventional magnetic tunnel junctions. This is particularly relevant given the increasing power consumption of technologies like generative AI. The need for energy-efficient devices is crucial for the future of computing.
