2021 Fiscal Year Annual Research Report

Characterization of Coupling between Mechanical Angular Momentum and Electron Spin

Research Project

Project/Area Number	19J21720
Research Institution	The University of Tokyo
Principal Investigator	許明然東京大学, 新領域創成科学研究科, 特別研究員(DC1)
Project Period (FY)	2019-04-25 – 2022-03-31
Keywords	magneto-rotation / magnon-phonon coupling / mgneto-elastic coupling / non-reciprocity
Outline of Annual Research Achievements	Microscopically, magnon-phonon coupling (MPC) is the force that correlates lattice and spin, i.e., associating magnetic energy. In recent, we observed a significant nonreciprocal behavior in MPC, which cannot be explained with conventional magneto-elastic coupling (MEC) based model, but can be fitted into the long time forgotten predication with magneto-rotation coupling (MRC). To further understand MRC and its connection with MEC, we performed a series MPC experiment on series NiFe alloys with modulated composition ratio. Systematic modulation of nonreciprocity has been observed. Besides, towards the application of MPC nonreciprocity, we designed and conduct a experiment with on a CoFeB(20 nm) thin film, where a magnetically controllable acoustic diode has been achieved.
Research Progress Status	令和3年度が最終年度であるため、記入しない。
Strategy for Future Research Activity	令和3年度が最終年度であるため、記入しない。