Magnetic skyrmions are vortex-like spin structures that are topologically stable. They have become an important topic in condensed matter physics because of their special properties and possible use in spintronics. In the chiral magnet MnSi, skyrmions form a regular lattice with a period of 18 nm. This lattice can be observed in real space by Lorentz transmission electron microscopy, and in...
The phase of the quantum-mechanical wave function can encode a topological structure with wide-ranging physical consequences, such as anomalous transport effects and the existence of edge states robust against perturbations. While this has been exhaustively demonstrated for electrons, properties associated with the elementary quasiparticles in magnetic materials are still underexplored. In our...
Altermagnets, a new type of unconventional collinear antiferromagnet with spin-splitting arising from non-relativistic symmetry breaking effects, have recently attracted tremendous interests in magnetism and spintronics. Unconventional magnetism actually goes beyond altermagnets, and can also be found in some non-collinear antiferromagnets that possess spin-orbit coupling (SOC). In this talk,...
We present an X-ray and neutron scattering study of the structure and magnetic excitations of Nd2PdSi3 [1], a sister compound of Gd2PdSi3 which was recently found to host a skyrmion phase despite its centrosymmetric crystal structure. Dispersive magnetic excitations corresponding to the complete crystal field scheme of the Nd atoms were measured throughout the reciprocal space Brillouin zone....
CeAlGe crystallizes in a tetragonal structure I41md, where the spatial-inversion symmetry is broken, and is expected to exhibit Weyl fermions near a Fermi surface that becomes more stable by broken time-reversal symmetry [1]. It has been known that the magnetic ground state and relevant topological properties of CeAlGe depend on the chemical stoichiometry. For example, CeAlGe grown by the flux...
Skyrmions are topological solitons with particle-like properties holding potential for applications in magnetic and quantum technologies. Recently, the quantum properties of skyrmions have garnered significant attention. Unlike their classical counterparts, quantum skyrmions exhibit novel physical phenomena arising from their entanglement properties of the underlying spin system – spin-1/2...
