[19a-D104-1~11] CS6 10.1 & 10.2 & 10.3 Code-sharing session

▲ [19a-D104-1] [Young Scientist Presentation Award Speech] Voltage control of perpendicular magnetic anisotropy in Fe/MgAl₂O₄ heterostructures

〇Qingyi Xiang^1,2, Hiroaki Sukegawa¹, Muftah Al-Mahdawi¹, Mohamed Belmoubarik¹, Shinya Kasai¹, Yuya Sakuraba¹, Seiji Mitani^1,2, Kazuhiro Hono^1,2 (1.NIMS, 2.Univ. of Tsukuba)

Keywords:VCMA, MgAl2O4, thin films

Voltage-controlled magnetic anisotropy (VCMA) in magnetic heterostructures are expected to be a key for approaching next generation low-power consumption spintronic devices such as voltage-controlled magnetoresistive random access memories (MRAMs). For practical high-density memory applications, large interface perpendicular magnetic anisotropy (PMA) energy K_i and voltage control of magnetic anisotropy (VCMA) coefficient β, i.e., K_i > 2-3 mJ/m² and β > 1000 fJ/(Vm), are required. To achieve such a large VCMA effect, investigating the origin of the VCMA effect using ideal PMA heterostructures without any interfacial defects appears to be necessary. In this study, we focused on the ultrathin-Fe/MgAl₂O₄(001) epitaxial interfaces to achieve high K_i and K_i. Especially, we investigated the Fe thickness dependence of VCMA using Fe/MgAl₂O₄/CoFeB orthogonally magnetized MTJs. We report that only a monolayer thickness difference has a significant impact on the PMA energy and VCMA effect.