论文标题
旋转波袋在准2D抗铁磁铁中的传播
Spin wavepacket propagation in quasi-2D antiferromagnets
论文作者
论文摘要
抗铁磁铁是通过自旋波传播信息的有吸引力的平台，其优势比响应速度和对外部场的免疫力提供了优于铁磁体。一项对准2D抗铁磁铁CRSBR的研究报告说，自旋波袋的群速度比通过非弹性中子散射获得的磁化分散体高的数量级传播[1,2]。在这里，我们表明，通过考虑远距离磁性偶极 - 偶极 - 偶极相互作用来自然解释组速度的异常大小和各向异性。我们还证明，可以通过施加外部磁场或改变样品厚度来通过数量级调整V_G。除了自旋波袋传播外，偶极相互作用还会在抗铁磁铁中产生非平衡bose-Einstein凝结的可能性，以前被认为是铁磁体所特有的特性。
Antiferromagnets are attractive platforms for the propagation of information via spin waves, offering advantages over ferromagnets in speed of response and immunity to external fields. A recent study of the quasi-2D antiferromagnet CrSBr reported that spin wavepackets propagate with group velocities that are orders of magnitude higher than expected from the magnon dispersion obtained by inelastic neutron scattering [1,2]. Here we show that the anomalous magnitude and anisotropy of the group velocity, v_g, are naturally explained by considering the long-range magnetic dipole-dipole interaction. We also demonstrate that v_g can be tuned over orders of magnitude by applying an external magnetic field or varying the sample thickness. Beyond spin wavepacket propagation, the dipolar interaction creates the possibility of non-equilibrium Bose-Einstein condensation in antiferromagnets, previously thought to be a property unique to ferromagnets.
