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Light-driven ultrafast phonomagnetism

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 نشر من قبل Dmytro Afanasiev
 تاريخ النشر 2019
  مجال البحث فيزياء
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Exciting atomic oscillations with light is a powerful technique to control the electronic properties of materials, leading to remarkable phenomena such as light-induced superconductivity and ultrafast insulator to metal transitions. Here we show that light-driven lattice vibrations can be utilised to encode efficiently spin information in a magnetic medium. Intense mid-infrared electric field pulses, tuned to resonance with a vibrational normal mode of antiferromagnetic DyFeO3, drive the emergence of long-living weak ferromagnetic order. Light-driven phonon displacements promptly lower the energy barrier separating competing magnetic states, allowing the alignment of spins to occur within a few picoseconds, via non-equilibrium dynamics of the magnetic energy landscape.



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