Determination of spin chirality using x-ray magnetic circular dichroism

Abstract

A 3-fold symmetric kagome lattice that has negative spin chirality can give a non-zero x-ray magnetic circular dichroism (XMCD) signal, despite that the total spin moment amounts to zero. This is explained by a hitherto unnoticed rule for the rotational symmetry invariance of the XMCD signal. A necessary condition is the existence of an anisotropic XMCD signal for the local magnetic atom, which can arise from a spin anisotropy either in the ground state or the final state. The angular dependence of the XMCD as a function of the beam direction has an unusual behavior. The maximum dichroism is not aligned along the spin direction, but depends on the relative orientation of the spin with respect to the atomic orientation. Therefore, different geometries can result in the same angular dependence, and the spin direction can only be determined if the atomic orientation is known. The consequences for the x-ray magneto-optical sum rules are given. The integrated XMCD signals are proportional to the anisotropy in the orbital moment and the magnetic dipole term, where the isotropic spin moment drops out.

7 pages, 5 figures

References in corpus (7)

• Perspective on Metallic Antiferromagnets
• Chirality-driven orbital magnetic moments as a new probe for topological magnetic structures
• Anomalous Hall Effect due to the spin chirality in the Kagomé lattice
• Generic nearest-neighbour kagome model: XYZ & Dzyaloshinskii-Moriya, and comparison to pyrochlore
• Magneto-optic and transverse transport properties of non-collinear antiferromagnets
• Presence of x-ray magnetic circular dichroism effect for zero-magnetization state in antiferromagnetism
• Ordered ground states of kagome magnets with generic exchange anisotropy

Cited by in corpus (5)

• X-ray Magnetic Circular Dichroism in Altermagnetic $\alpha$-MnTe
• Electronic chiralization as an indicator of the anomalous Hall effect in unconventional magnetic systems
• Antiferromagnetic real-space configuration probed by dichroism in scattered x-ray beams with orbital angular momentum
• Giant X-ray circular dichroism in a time-reversal invariant altermagnet
• X-ray magnetic circular dichroism originating from the $T_z$ term in collinear altermagnets under trigonal crystal field