A study published in Nature Materials reveals a new method for precisely tuning magnetism using CrPS₄, paving the way for faster, smaller, and more energy-efficient smart magnetic technologies. CrPS₄ is an ultra-thin material just a few atoms thick, and researchers have discovered that magnetic behavior can be precisely controlled simply by altering the internal layer arrangement of CrPS₄ — without the need to stack different materials.
Magnetism is at the heart of digital memory, but controlling magnetic behavior — especially the exchange bias phenomenon — has long been a scientific challenge. In traditional approaches, exchange bias occurs at buried, imperfect interfaces between different materials, making it difficult to study and control. In this research, however, CrPS₄ naturally forms regions with different magnetic properties depending on thickness within a single ultra-thin flake. Using nitrogen-vacancy (NV) center magnetometry, an advanced imaging technique, the team observed how magnetic domains form, interact, and move at boundaries between layers of different thickness. This discovery allows researchers to turn exchange bias on or off like a switch — in a fully controllable and reversible manner.
Dr. Elton Santos from the University of Edinburgh's School of Physics and Astronomy compared the regions inside CrPS₄ to lanes on a highway, with boundaries between them forming a perfect interface that enables unprecedented precision in studying and controlling magnetic behavior. This breakthrough not only deepens scientific understanding of magnetism but also lays the foundation for building smarter, smaller, and more reliable magnetic devices. CrPS₄ is stable in air and easy to handle, making it an ideal candidate for real-world applications. The researchers say this discovery could drive the development of ultra-compact memory chips, reconfigurable sensors, and even quantum computing devices based on magnetic principles. Dr. Santos emphasized: "This breakthrough opens a window into the invisible world of atomic-scale magnetism and unlocks the door to entirely new magnetic technologies."
