Hansen Ursula B, Syljuåsen Olav F, Jensen Jens, Schäffer Turi K, Andersen Christopher R, Boehm Martin, Rodriguez-Rivera Jose A, Christensen Niels B, Lefmann Kim
Niels Bohr Institute, University of Copenhagen, Universitetsparken 5, 2100, Copenhagen, Denmark.
Institut Laue-Langevin, CS 20156, 38042, Grenoble Cedex 9, France.
Nat Commun. 2022 May 10;13(1):2547. doi: 10.1038/s41467-022-29854-9.
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 ferromagnetic easy axis chain. In this case, the "particles" undergoing oscillatory motion in the presence of a magnetic field are domain walls. 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.
当周期性晶格中的带电粒子受到恒定电场作用时，它们会通过振荡做出响应。在此，我们证明了这些布洛赫振荡的磁类似物在铁磁易轴链中得以实现。在这种情况下，在磁场存在下进行振荡运动的“粒子”是畴壁。非弹性中子散射揭示了低能自旋动力学的三个不同分量，包括标志性的布洛赫振荡模式。通过无参数的理论计算，我们能够解释激发谱中的所有特征，从而为自旋各向异性链中的复杂动力学提供详细的见解。
