2016/02/29 by Jens Paaske, Erikas Gaidamauskas
Physics and Astronomy · #Advanced Condensed Matter Physics #Anisotropy #Condensed matter physics #Image warping #Magnetic anisotropy #Magnetic field #Magnetization #Materials science #Optics #Physics #Quantum many-body systems #Quantum mechanics #Scattering #Topological Materials and Phenomena #Topological insulator #cond-mat.mes-hall
paper · pdf · doi:10.1103/physrevlett.117.177201
published as Phys. Rev. Lett. 117, 177201 (2016) · 5 pages, 3 figures
openalex publication_date 2016/10/20 · arxiv created 2016/10/21 · arxiv updated 2016/10/24 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We show that higher-harmonics exchange scattering from a magnetic adatom on the surface of a three dimensional topological insulator leads to a magnetic anisotropy whose magnitude and sign may be tuned by adjusting the chemical potential of the helical surface band. As the chemical potential moves from the Dirac point towards the surface band edge, the surface normal is found to change from a magnetic easy to a hard axis. Hexagonal warping is shown to diminish the region with easy axis anisotropy, and to suppress the anisotropy altogether. This indirect contribution can be comparable in magnitude to the intrinsic term arising from crystal field splitting and atomic spin-orbit coupling, and its tunability with the chemical potential makes the two contributions experimentally discernible, and endows this source of anisotropy with potentially interesting magnetic functionality.