近日，美国加州大学的Joseph Orenstein及其研究团队取得一项新进展。经过不懈努力，他们揭示范德华反铁磁体中的偶极自旋波包传输过程。相关研究成果已于2024年2月1日在国际知名学术期刊《自然—物理学》上发表。

该研究团队通过实验证明了磁振子的传播是由远距离偶极子-偶极子相互作用介导的。这种耦合是基本电动力学的必然结果，因此，在目前正在研究的所有范德华磁体中，这种耦合都可能成为长波长自旋传播的媒介。研究人员成功地揭示了自旋传播的机制，并提供了一套优化规则和注意事项，这对于这些具有前景的系统的未来应用至关重要

据悉，反铁磁体作为一种有潜力的平台，通过磁振子（自旋波的量子）进行量子信息的转导和传输，在耗散、响应速度和对外部场的鲁棒性方面具有优于铁磁体的优势。最近，在范德华反铁磁体中实现了光子与磁振子的转导，其中强自旋激子耦合使得可见光光子能够读取相干磁振子的振幅和相位。这一发现将研究的重点转移到了传输上，特别是探索使磁振子波包传播的非局部相互作用。

附：英文原文

Title: Dipolar spin wave packet transport in a van der Waals antiferromagnet

Author: Sun, Yue, Meng, Fanhao, Lee, Changmin, Soll, Aljoscha, Zhang, Hongrui, Ramesh, Ramamoorthy, Yao, Jie, Sofer, Zdenk, Orenstein, Joseph

Issue&Volume: 2024-02-01

Abstract: Antiferromagnets are promising platforms for transduction and transmission of quantum information via magnons—the quanta of spin waves—and they offer advantages over ferromagnets in regard to dissipation, speed of response and robustness to external fields. Recently, transduction was shown in a van der Waals antiferromagnet, where strong spin-exciton coupling enables readout of the amplitude and phase of coherent magnons by photons of visible light. This discovery shifts the focus of research to transmission, specifically to exploring the non-local interactions that enable magnon wave packets to propagate. Here we demonstrate that magnon propagation is mediated by long-range dipole–dipole interaction. This coupling is an inevitable consequence of fundamental electrodynamics and, as such, will likely mediate the propagation of spin at long wavelengths in the entire class of van der Waals magnets currently under investigation. Successfully identifying the mechanism of spin propagation provides a set of optimization rules, as well as caveats, that are essential for any future applications of these promising systems.

DOI: 10.1038/s41567-024-02387-2

Source: https://www.nature.com/articles/s41567-024-02387-2