A new scientific review describes how light and magnetism interact in materials only a few atoms thick. Researchers at the City College of New York highlight ways excitons can influence magnetic states. The work points to possible uses in quantum devices and optical memory.
The review, published in Nature Materials, examines van der Waals magnetic semiconductors. In these crystals, light-generated excitons share electronic origins with magnetic moments, allowing direct interactions.
Lead author Pratap Chandra Adak said an exciton "can sense the spin order and magnons, and under the right conditions, even help control the magnetic state itself." Senior author Vinod M. Menon noted the field has shifted from detecting magnetism to exploring active control of light-matter interactions.
Platforms such as chromium triiodide and chromium sulfur bromide show excitons strengthening magneto-optical effects. Potential applications include magneto-photonic memory, all-optical logic, and quantum transducers that convert microwave signals to optical frequencies.
The research received support from DARPA and the Gordon and Betty Moore Foundation. Co-authors include researchers from the Technical University of Munich and the University of Washington.
