(1. Hefei Innovation Research Institute, Beihang University, Hefei 230012, China ) (2. School of Integrated Circuit Science and Engineering, Beihang University, Beijing 100191, China)
Nowadays, the working frequency of spintronic devices becomes higher and higher, so that ultrafast spin dynamics in magnetic materials is as one of research focuses in condensed matter physics. Meanwhile, ultrafast spin dynamics in magnetic materials induced by femtosecond laser pulse is rich in physical meaning. It involves the basic problem of multiparticle quantum interaction among electrons, phonons and spins under non-equilibrium state. As a result, a new direction in magnetism has been founded as femtosecond-magnetism. Based on the above, the main progresses and important applications of ultrafast spin dynamics induced by femtosecond laser pulse were reviewed, including experimental equipments, theoretical and experimental models, as well as all-optical magnetization reversal effect. Therefore, in order to explore the micro-mechanism of ultrafast spin dynamics in a deeper level, a new research model should be established to develop direct descriptions. Furthermore, a crucial task is to find out new materials with high thermal stability, high spin polarization, low power consumption and high storage rate. Therefore, novel spintronic devices with low power consumption and ultrafast response could be designed in the near future.