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

由Onose等人发现的磁振子霍尔效应已经在各种铁磁绝缘体中进行了研究。我们已经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相互作用诱导的磁振子的Berry相来解释。此外，我们还建立了微波测量系统，可以在低温下测量磁场下微波对磁振子的共振激发。利用它，我们在斯基米子晶格的拓扑磁性态中观察到了独特的磁振子模式（斯基米子旋转模式、斯基米子呼吸模式）。

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.