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Magnetic Bloch Oscillations and domain wall dynamics in a near-Ising ferromagnetic chain

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 نشر من قبل Ursula Bengaard Hansen
 تاريخ النشر 2019
  مجال البحث فيزياء
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When charged particles in periodic lattices are subjected to a constant electric field, they respond by oscillating. Here we demonstrate that the magnetic analogue of these Bloch oscillations are realised in a one-dimensional ferromagnetic easy axis chain. In this case, the particle undergoing oscillatory motion in the presence of a magnetic field is a domain wall. Inelastic neutron scattering reveals three distinct components of the low energy spin-dynamics including a signature Bloch oscillation mode. Using parameter-free theoretical calculations, we are able to account for all features in the excitation spectrum, thus providing detailed insights into the complex dynamics in spin-anisotropic chains.

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