||高橋 陽太郎 准教授
||Magneto-optical response of massive Dirac fermions in kagome magnets
||Light combines with magnetism to produce magneto-optical effects such as the magneto-optical Kerr effect and the Faraday effect. This effect has been applied to technologies such as optical isolators, magnetic domain imaging, and MO disks. Under these circumstances, in the field of material science, the concept of topology, which deals with invariant properties due to continuous deformation, has been attracting attention in recent years, and topological electrons such as Dirac/Weyl fermion have been found in the band structure of k-space.
In recent years, it has been recognized that this Dirac Weyl fermion plays an important role in nonlinear optical responses such as high-order harmonic generation and photocurrent . Topological electronic structure can be regarded as having a magnetic monopole in the k-space, and it is expected that it will be strongly coupled with the magneto-optical response and new charge dynamics will be generated .
In this presentation, we will describe the characteristic magneto-optical responses of RMn6Sn6 (R = Tb,Dy), kagome lattice magnets with massive Dirac fermions from lattice geometry.
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