Abstract
The orbital angular momenta (OAM) of electrons play an increasingly important role in ultrafast electron and magnetization dynamics. In this theoretical study, we investigate the electron dynamics induced by femtosecond laser pulses in a normal metal, a ferromagnet, and a ferromagnet/normal metal heterostructure. We analyze the spatiotemporal distributions of the laser-induced OAM and their respective currents. Our findings demonstrate that a circularly polarized laser pulse can induce a sizable and long-lasting OAM component in a normal metal. Furthermore, an interface between a ferromagnet and a normal metal facilitates the demagnetization of the magnet by the OAM contribution to the total magnetization. Finally, to transfer OAM from a ferromagnet into a normal metal, it is advantageous to use a laser setup that induces the desired OAM component in the ferromagnet, but not in the normal metal.
- Received 23 June 2023
- Revised 17 August 2023
- Accepted 28 August 2023
DOI:https://doi.org/10.1103/PhysRevB.108.104408
©2023 American Physical Society