Light-Induced Phonon-Mediated Magnetization in Monolayer MoS2

Light-induced ultrafast spin dynamics in materials is of great importance for developments of spintronics and magnetic storage technology. Recent progresses include ultrafast demagnetization, magnetic switching, and magnetic phase transitions, while the ultrafast generation of magnetism is hardly achieved. Here, a strong light-induced magnetization (up to 0.86 mu (B) per formula unit) is identified in non-magnetic monolayer molybdenum disulfide (MoS2). With the state-of-the-art time-dependent density functional theory simulations, we demonstrate that the out-of-plane magnetization can be induced by circularly polarized laser, where chiral phonons play a vital role. The phonons strongly modulate spin-orbital interactions and promote electronic transitions between the two conduction band states, achieving an effective magnetic field similar to 380 T. Our study provides important insights into the ultrafast magnetization and spin-phonon coupling dynamics, facilitating effective light-controlled valleytronics and magnetism.