Laser induced ultrafast magnetization reversal in TbCo film

All optical switching is an emerging recording technology by using femtosecond laser to realize ultrafast magnetization manipulation for super-high magnetic storage. TbCo films possess ferrimagnetic structure and large perpendicular anisotropy and thus have the potential to be used as a AOS material. In this paper, we simulate the ultrafast magnetization reversal of TbCo films under 100fs pulse laser with a general theoretical framework and the simulated results show that TbCo films can generate magnetization reversal at the timescale of several ps. Co-sublattice completes demagnetization and subsequently triggers magnetize reversal within 1.0ps, whereas Tb- sublattice begins to magnetize reversal more than 4.0ps. Moreover, large laser power intensity easily induce the complete demagnetization and subsequent magnetization reversal regardless of the composition of TbCo films.