Tuning ultrafast demagnetization with ultrashort spin polarized currents in multi-sublattice ferrimagnets.

ABSTRACT: Femtosecond laser pulses can be used to induce ultrafast changes of the magnetization in magnetic materials. Several microscopic mechanisms have been proposed to explain these observations, including the transport of ultrashort spin-polarized hot-electrons (SPHE). However, currently such ultrafast spin currents are only poorly characterized due to the measurement requirements for element and time resolution. Here, using time- and element-resolved X-ray magnetic circular dichroism alongside atomistic spin-dynamics simulations, we study the ultrafast transfer of the angular momentum from spin-polarized currents. We show that using a Co/Pt multilayer as a polarizer in a spin-valve structure, the SPHE drives the demagnetization of the two sub-lattices of the Fe₇₄Gd₂₆ film

SUBMITTER: Gupta D 

PROVIDER: S-EPMC11958827 | biostudies-literature | 2025 Mar

REPOSITORIES: biostudies-literature