Anomalous magnon transport phenomena induced by the Berry phase and exploration of related material functionality

由Onous等人发现的Magnon Hall效应已被用于各种铁磁绝缘体的研究。我们观察到晶格几何对磁振子霍尔效应的独特影响，并表明它可以用Dzyaloshinskii-Moriya相互作用引起的磁子的Berry相来解释。此外，我们还建立了微波测量系统，可以在低温磁场作用下测量微波对磁子的共振激发。利用它，我们观察到了Skyrmion晶格拓扑磁状态中独特的磁振子模式(Skyrmion旋转模、Skyrmion呼吸模)。

Magnon Hall effect, which was discovered by Onose et al., have been investigated for various ferromagnetic insulators. We have observed the distinctive effect of lattice geometry on magnon Hall effect and show that it can be explained in terms of the Berry phase of magnons induced by Dzyaloshinskii-Moriya interaction. In addition, we have setup the microwave measurement system, in which we can measure the resonant excitation of magnons by microwave under the magnetic field at low temperature. With use of it, we have observed unique magnon modes (skyrmion rotation mode, skyrmion breathing mode) in a topological magnetic state of skyrmion lattice.