Terahertz charge and spin transport in metallic ferromagnets: The role of crystalline and magnetic order

  title={Terahertz charge and spin transport in metallic ferromagnets: The role of crystalline and magnetic order},
  author={Kumar Neeraj and Apoorva Sharma and Maria J. Almeida and Patrick Matthes and Fabian Samad and Georgeta Salvan and Olav Hellwig and Stefano Bonetti},
  journal={Applied Physics Letters},
We study the charge and spin dependent scattering in a set of CoFeB thin films whose crystalline order is systematically enhanced and controlled by annealing at increasingly higher temperatures. Terahertz conductivity measurements reveal that charge transport closely follows the development of the crystalline phase, with the increasing structural order leading to higher conductivity. The terahertz-induced ultrafast demagnetization, driven by spin-flip scattering mediated by the spin–orbit… 
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