Terahertz spin ratchet effect in magnetic metamaterials

0583245 - FZÚ 2024 RIV US eng J - Journal Article
Hild, M. - Golub, L.E. - Fuhrmann, A. - Otteneder, M. - Kronseder, M. - Matsubara, M. - Kobayashi, T. - Oshima, D. - Honda, A. - Kato, T. - Wunderlich, Joerg - Back, C. - Ganichev, S. D.
Terahertz spin ratchet effect in magnetic metamaterials.
Physical Review B. Roč. 107, č. 15 (2023), č. článku 155419. ISSN 2469-9950. E-ISSN 2469-9969
Institutional support: RVO:68378271
Keywords : spin ratchet * metamaterials * anomalous Hall and Nernst effects
OECD category: Condensed matter physics (including formerly solid state physics, supercond.)
Impact factor: 3.7, year: 2022
Method of publishing: Limited access
https://doi.org/10.1103/PhysRevB.107.155419

We report on spin ratchet currents driven by terahertz radiation electric fields in a Co/Pt magnetic metamaterial formed by triangle-shaped holes forming an antidot lattice and subjected to an external magnetic field applied perpendicularly to the metal film plane. We show that for a radiation wavelength substantially larger than the period of the antidots array, the radiation causes a polarization-independent spin-polarized ratchet current. The current is generated by the periodic asymmetric radiation intensity distribution caused by the near-field diffraction at the edges of the antidots, which induces spatially inhomogeneous periodic electron gas heating, and a phase-shifted periodic asymmetric electrostatic force. The developed microscopic theory shows that the magnetization of the Co/Pt film results in a spin ratchet current caused by both the anomalous Hall and the anomalous Nernst effects.
Permanent Link: https://hdl.handle.net/11104/0351250