Scientists manipulate magnets at the atomic scale

Science Daily  February 12, 2021 An international team of researchers (the Netherlands, Ukraine, Russia, Belgium, UK) shows that light-driven phonons can be utilized to coherently manipulate macroscopic magnetic states. Intense mid-infrared electric field pulses tuned to resonance with a phonon mode of the archetypical antiferromagnet DyFeO3 induce ultrafast and long-living changes of the fundamental exchange interaction between rare-earth orbitals and transition metal spins. Non-thermal lattice control of the magnetic exchange, which defines the stability of the macroscopic magnetic state, allows picosecond coherent switching between competing antiferromagnetic and weakly ferromagnetic spin orders. The discovery emphasizes the potential of resonant phonon excitation […]

Magnetic nanoparticles change their magnetic structure in a magnetic field

Nanowerk  July 27, 2020 Up to now, scientists assumed that magnetism in a nanoparticle is essentially limited to this core area. Using neutron scattering on cobalt ferrite nanoparticles an international team or researchers (France, Germany, Czech Republic) has shown that the applied magnetic field causes some of the previously disordered magnetic moments in the surface region to become aligned, and thus ordered in a way comparable to the magnetization in the core region. However, a residual area with differently aligned spins remains on the surface, which cannot be ordered by the applied magnetic field. Overall, the research showed that the […]