Twists in Ferromagnetic Monolayers With Trigonal Prismatic Symmetry

Abstract

Two-dimensional materials such as graphene or hexagonal boron nitride are indispensable in industry. The recently discovered 2D ferromagnetic materials also promise to be vital for applications. In this work, we develop a phenomenological description of non-centrosymmetric 2D ferromagnets with trigonal prismatic crystal structure. We chose to study this special symmetry group since these materials do break inversion symmetry and therefore, in principle, allow for chiral spin structures such as magnetic helices and skyrmions. However, unlike all non-centrosymmetric magnets known so far, we show that the symmetry of magnetic trigonal prismatic monolayers neither allow for an internal relativistic Dzyaloshinskii-Moriya interaction (DMI) nor a reactive spin-orbit torque. We demonstrate that the DMI only becomes important at the boundaries, where it modifies the boundary conditions of the magnetization and leads to a helical equilibrium state with a helical wavevector that is inherently linked to the internal spin orientation. Furthermore, we find that the helical wavevector can be electrically manipulated via dissipative spin-torque mechanisms. Our results reveal that 2D magnets offer a large potential for unexplored magnetic effects.

arXiv comment5 pages, 3 figures

References in corpus (22)

• Electric Field Effect in Atomically Thin Carbon Films
• 2D materials and van der Waals heterostructures
• Layer-dependent Ferromagnetism in a van der Waals Crystal down to the Monolayer Limit
• Discovery of intrinsic ferromagnetism in 2D van der Waals crystals
• Advances in the Physics of Magnetic Skyrmions and Perspective for Technology
• Spin Transfer Torques
• Evidence of Ising pairing in superconducting NbSe${}_2$ atomic layers
• Skyrmion confinement in ultrathin film nanostructures in the presence of Dzyaloshinskii-Moriya interaction
• Skyrmions in Magnetic Multilayers
• The properties of isolated chiral skyrmions in thin magnetic films
• Collective spin excitations of helices and magnetic skyrmions: review and perspectives of magnonics in non-centrosymmetric magnets
• Three-dimensional skyrmion states in thin films of cubic helimagnets
• Surface twist instabilities and skyrmion states in chiral ferromagnets
• Chiral surface twists and skyrmion stability in nanolayers of cubic helimagnets
• Edge states and skyrmion dynamics in nanostripes of frustrated magnets
• Edge instabilities and skyrmion creation in magnetic layers
• Helimagnon Bands as Universal Spin Excitations of Chiral Magnets
• Phenomenology of Current-Induced Spin-Orbit Torques
• Spin-Motive Forces and Current-Induced Torques in Ferromagnets
• Neutron study of in-plane skyrmions in MnSi thin films
• Boundary-Driven Twist States in Systems with Broken Spatial Inversion Symmetry
• The effect of boundary-induced chirality on magnetic textures in thin films

Cited by in corpus (8)

• Néel-type skyrmions and their current-induced motion in van der Waals ferromagnet-based heterostructures
• Chiral ferromagnetism beyond Lifshitz invariants
• Helitronics for classical and unconventional computing
• Current-induced H-shaped-skyrmion creation and their dynamics in the helical phase
• Current-Induced Dynamics of Chiral Magnetic Structures: Creation, Motion, and Applications
• Quartic asymmetric exchange for two-dimensional ferromagnets with trigonal prismatic symmetry
• Large Surface Magnetization in Noncentrosymmetric Antiferromagnets
• Signatures of quartic asymmetric exchange in a class of two dimensional magnets