El Kanj Aya, Gomonay Olena, Boventer Isabella, Bortolotti Paolo, Cros Vincent, Anane Abdelmadjid, Lebrun Romain
Unité Mixte de Physique, CNRS, Thales, Université Paris-Saclay, 91767 Palaiseau, France.
Institute of Physics, Johannes Gutenberg-University Mainz, 55128 Mainz, Germany.
Sci Adv. 2023 Aug 11;9(32):eadh1601. doi: 10.1126/sciadv.adh1601.
Spin-waves in antiferromagnets hold the prospects for the development of faster, less power-hungry electronics and promising physics based on spin superfluids and coherent magnon condensates. For both these perspectives, addressing electrically coherent antiferromagnetic spin-waves is of importance, a prerequisite that has been so far elusive, because, unlike ferromagnets, antiferromagnets couple weakly to radiofrequency fields. Here, we demonstrate the detection of ultra-fast nonreciprocal spin-waves in the dipolar exchange regime of a canted antiferromagnet using both inductive and spintronic transducers. Using time-of-flight spin-wave spectroscopy on hematite (α-FeO), we find that the magnon wave packets can propagate as fast as 20 kilometers/second for reciprocal bulk spin-wave modes and up to 6 kilometers/second for surface spin-waves propagating parallel to the antiferromagnetic Néel vector. We lastly achieve efficient electrical detection of nonreciprocal spin-wave transport using nonlocal inverse spin-Hall effects. The electrical detection of coherent nonreciprocal antiferromagnetic spin-waves paves the way for the development of antiferromagnetic and altermagnet-based magnonic devices.
反铁磁体中的自旋波为开发速度更快、功耗更低的电子器件以及基于自旋超流体和相干磁振子凝聚体的前沿物理学带来了希望。从这两个角度来看，解决电相干反铁磁自旋波至关重要，而这一先决条件迄今难以实现，因为与铁磁体不同，反铁磁体与射频场的耦合较弱。在此，我们展示了利用电感式和自旋电子换能器在倾斜反铁磁体的偶极交换区域中检测超快非互易自旋波。通过对赤铁矿（α-FeO）进行飞行时间自旋波光谱分析，我们发现，对于互易体自旋波模式，磁振子波包的传播速度可达20千米/秒，而对于平行于反铁磁奈尔矢量传播的表面自旋波，其传播速度可达6千米/秒。最后，我们利用非局域逆自旋霍尔效应实现了对非互易自旋波输运的高效电检测。相干非互易反铁磁自旋波的电检测为基于反铁磁体和异磁体的磁振子器件的发展铺平了道路。
