0000000000033801
AUTHOR
Victor Spetter
Resolving the Fundamentals of Magnetotransport in Metals with Ultrafast Terahertz Spectroscopy
Using terahertz spectroscopy we directly resolved the fundamentals of spin-dependent conductivity in ferromagnetic metals. We quantified the differences in conduction by Fermi-level electrons with opposite spins on the sub-100 fs timescale of electron momentum scattering.
Probing giant magnetoresistance with THz spectroscopy
We observe a giant magnetoresistance effect in CoFe/Cu-based multistack using THz time-domain spectroscopy. The magnetic field-dependent dc conductivity, electron scattering time, as well as spin-asymmetry parameter of the structure are successfully determined.
Accessing the fundamentals of magnetotransport in metals with terahertz probes
Spin-dependent conduction in metals underlies all modern magnetic memory technologies, such as giant magnetoresistance (GMR). The charge current in ferromagnetic transition metals is carried by two non-mixing populations of sp-band Fermi-level electrons: one of majority-spin and one of minority-spin. These electrons experience spin-dependent momentum scattering with localized electrons, which originate from the spin-split d-band. The direct observation of magnetotransport under such fundamental conditions, however, requires magnetotransport measurements on the same timescale as the electron momentum scattering, which takes place in the sub-100 fs regime. Using terahertz electromagnetic prob…