Linearly polarized light-induced magnetism in bilayer MoSe₂.

Linearly polarized light transiently induces magnetism in bilayer MoSe₂ by breaking time-reversal symmetry through interlayer phonon coupling.

• Why it matters: Understanding how to manipulate non-magnetic van der Waals materials expands possibilities for dynamic control of material properties and novel functionalities in 2D systems.
• What they did: The study used ultrafast measurements and first-principles simulations to show that linearly polarized light excites coherent interlayer phonons, leading to symmetry breaking and effective magnetization.
• The result: This discovery reveals a new light-driven pathway for controlling interlayer interactions and magnetism in van der Waals crystals, paving the way for light-on-demand functionalities in layered 2D materials.