![]() NCTS (South) | |
DATE | 2015-03-02 |
TIME | 14:00 |
PLACE | 物理二館地下室 (49X04) |
FIELD | Other |
SPEAKER | 莊子弘 - RIKEN SPring-8 Center, Japan |
TITLE | High wave-vector magnon excitations in low-dimensional ferromagnets |
ABSTRACT | First, a combined experimental and theoretical study of the interplay between the atomic structure and the magnon excitations in low-dimensional ferromagnets is presented. First-principles calculations confirm the experimental results revealing a strong dependency of exchange interactions on the atomic structure. Our results suggest a way of tailoring magnetic excitations in low-dimensional magnetic structures. Second, we propose a method for probing the magnetic exchange interaction at buried interfaces using spin-polarized electrons and taking advantage of the collective nature of elementary magnetic excitations (magnons). We demonstrate that, for the case of weak coupling at the interface, the low-energy magnon mode is mainly localized at the interface. The comparison of experimental data and first-principles calculations leads to the determination of the interface exchange parameters. This method may help the development of spectroscopy of buried magnetic interfaces. |