Tunable layered-magnetism–assisted magneto-Raman effect in a two-dimensional magnet CrI <sub>3</sub>
Wencan Jin, Zhipeng Ye, Xiangpeng Luo, Bowen Yang, Gaihua Ye, Fangzhou Yin, Hyun Ho Kim, Laura Rojas, Shangjie Tian, Fu Yang, Shaohua Yan, Hechang Lei, Kai Sun, Adam W. Tsen, Rui He, Liuyan Zhao
Abstract
Significance The two-dimensional (2D) magnetic semiconductor CrI 3 hosts a variety of strong and tunable magneto-optical effects and allows for the development of novel magneto-optical devices. While the elastic magneto-optical effects in CrI 3 are well understood, its recently discovered inelastic magneto-Raman effect remains to have case-specific interpretations varying upon the thickness of CrI 3 . We perform comprehensive Raman measurements on 2D CrI 3 with polarization, temperature, layer number, and magnetic field dependence. We resolve a Davydov-split–induced N -fold multiplet in N -layer CrI 3 and reveal the distinct magneto-Raman behaviors of individual phonons within the multiplet. Our results discover a layered-magnetism–coupled phonon scattering mechanism that explains the rich magneto-Raman effect in CrI 3 of arbitrary thickness and elucidates the spin–phonon coupling physics in layered magnets.