Van der Waals magnetic semiconductors where light-driven excitons directly couple with, read, and control internal spin waves (magnons)

https://www.eurekalert.org/news-releases/1135941

"these optical and magnetic properties arise from the exact same electronic orbitals within the crystal lattice, so light and magnetism no longer operate as separate channels... coupling allows the light-driven excitons to actively sense the underlying spin order and, under the right conditions, fundamentally control the material's magnetic state... micro-technologies, including magneto-photonic computer memories, optical logic systems, and high-frequency optical quantum transducers"