[17p-Z19-8~24] 10.3 Spin devices, magnetic memories and storages

▲ [17p-Z19-19] Interfacial enhancement of g-factor at CoFeB/MgO characterized by a high sensitivity ferromagnetic resonance spectroscopy

〇Tatsuya Yamamoto¹, Shingo Tamaru¹, Takayuki Nozaki¹, Kay Yakushiji¹, Hitoshi Kubota¹, Akio Fukushima¹, Shinji Yuasa¹ (1.AIST)

Keywords:g-factor, perpendicular magnetic anisotropy, ferromagnetic resonance

In this work, we utilize custom-build vector network analyzer ferromagnetic resonance (VNA-FMR) measurement setup which is capable of field modulation detection for investigating the g-factors of CoFeB ultrathin films attached to an MgO layer. The highly sensitive VNA-FMR spectroscopy allows to determine the change in the g-factor as a function of CoFeB thickness. By comparing with the magnetic parameters obtained by a vibrating sample magnetometer, we also show that the enhancement of g-factor is associated with the perpendicular magnetic anisotropy at the CoFeB/MgO interface.