Light-Induced Phonon-Mediated Magnetization in Monolayer MoS₂

Abstract

Light-induced ultrafast spin dynamics in materials is of great importance for the 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 0.86μB per formula unit) has been 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 ~380 Tesla. Our study provides important insights into the ultrafast magnetization and spin-phonon coupling dynamics, facilitating effective light-controlled valleytronics and magnetism.

Circular Polarization-Resolved Raman Optical Activity: A Perspective on Chiral Spectroscopies of Vibrational States

“…Chiral phonons were theoretically predicted 39 and experimentally observed in transition-metal dichalcogenides (TMD), such as MoS 2 , and their twisted stacks. 40 , 41 Ishito and co-workers reported the use of circularly polarized Raman spectroscopy to determine the chirality and ROA of three-dimensional α-HgS, by measuring the phonon mode response and splitting. 42 These results revealed the importance of phonons in the spatial imaging of chiral domains in 2D nanostructures.…”

Synthesis Methods and Property Control of Two-Dimensional Magnetic Materials

“…[1] Single-layer graphene has had a profound impact on materials, physics, and chemistry. Researchers have since identified numerous 2D nanomaterials, including metals, semimetals, semiconductors, topological insulators, and insulators, such as MoS2, [2] WS2, MoSe2, Bi2Te3, h-BN, Fe3GeTe2, [3][4][5] Cr2GeTe6, [6] CrSBr, [7] and so on. [8][9][10][11] Their planar structures, unique properties, excellent optical and electrical characteristics, and wide-ranging applications in the field of energy have attracted a great deal of attention from many researchers.…”