電圧による交換相互作用と磁化の制御

点击翻译按钮获取中文摘要

Electric field control of magnetic properties in metallic ferromagnets is attracting much attention because of its potential to be a key technology to produce ultralow energy consumption spintronics devices. Especially voltage induced magnetic anisotropy changes in ferromagnetic metal system at room temperature, have been widely studied targeting an ultra-low power MRAM applications. It is widely studied voltage induced magnetic properties, but the voltage control of the exchange interaction in 3d ferromagnets is under discussion. Beside of this, such voltage control in Aex may provide us new functionality of magnetic materials such as voltage switching of ferromagnetism, creation and annihilation of skyrmions, control of magnon velocity, etc. So, JSPS fellow had investigated electric field induced magnetic properties changes on the magnetic tunnel junction with perpendicular magnetic free layer.Skyrmions are topologically protected spin textures which often originated from asymmetric exchange coupling as known Dzyaloshinskii-Moriya interaction. Recently, it has been attracted due to the possibility of the skyrmion based information devices and information storage units. The motion of the skyrmion on two-dimensional film can be described by a modified version of Newton’s equation. JSPS fellow had explored on the skyrmions dynamics under various force such as gradient external magnetic field, gradient magnetic parameters, applying current and thermal energy.