Ly Ousmane
Physical Science and Engineering Division (PSE), King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Saudi Arabia.
J Phys Condens Matter. 2023 Feb 1;35(12). doi: 10.1088/1361-648X/acb523.
We demonstrate the generation of high order harmonics in carrier pumping from precessing ferromagnetic or antiferromagnetic orders, excited via magnetic resonance, in the presence of topological antiferromagnetic textures. This results in an enhancement of the carrier dynamics by orders of magnitude, enabling for an emission deep in the THz frequency range. Interestingly, the generation process occurs in an intrinsic manner, and is solely governed by the interplay between the s-d exchange coupling underlying the noncollinear antiferromagnetic order and the dynamical s-d exchange constant of the magnetic drive. Therefore, the relativistic spin-orbit interaction is not required for the emergence of high harmonics in the pumped currents. Accordingly, the noncollinear topological antiferromagnetic order is presented as an alternative to spin-orbit interaction for the purpose of harnessing high harmonic emission in carrier pumping. Furthermore, we demonstrate the emergence of high harmonics from random magnetic impurities. This suggests the universality of the magnetically induced high harmonic emission in the presence of real and/or momentum space noncollinear textures. Our proposal initiates a tantalizing prospect for the utilization of topological textures in the context of the highly active domains of ultrafast spintronics and THz emission.
我们展示了在存在拓扑反铁磁纹理的情况下,通过磁共振激发的进动铁磁或反铁磁序在载流子泵浦中产生高次谐波。这导致载流子动力学增强了几个数量级,能够在太赫兹频率范围内深处发射。有趣的是,产生过程以固有方式发生,并且仅由非共线反铁磁序背后的s-d交换耦合与磁驱动的动态s-d交换常数之间的相互作用决定。因此,在泵浦电流中产生高次谐波不需要相对论自旋轨道相互作用。相应地,非共线拓扑反铁磁序被提出作为自旋轨道相互作用的替代方案,用于在载流子泵浦中利用高次谐波发射。此外,我们展示了从随机磁性杂质中出现高次谐波。这表明在存在实空间和/或动量空间非共线纹理的情况下,磁诱导高次谐波发射的普遍性。我们的提议为在超快自旋电子学和太赫兹发射的高活性领域中利用拓扑纹理开创了诱人的前景。