[5p-C18-8~21] 【CS.10】10.1 & 10.2 & 10.3 Code-sharing session

▼ [5p-C18-10] Voltage control of perpendicular magnetic anisotropy in Fe/MgAl₂O₄ heterostructures

〇(D)Qingyi Xiang^1,2, Sukegawa Hiroaki¹, Mufta Al-Mahdawi¹, Mohamed Belmoubarik¹, Shinya Kasai¹, Yuya Sakuraba¹, Seiji Mitani^1,2, Kazuhiro Hono^1,2 (1.NIMS, 2.Univ. Tsukuba)

Keywords:PMA, VCMA, Spinel

Perpendicular magnetic anisotropy (PMA) and its voltage control in magnetic heterostructures [1] are expected to be a key for achieving low-power consumption spintronic devices such as voltage-torque magnetoresistive random access memories (MRAMs). For actual high-density memory applications, large interface PMA energy (K_i) and voltage control of magnetic anisotropy (VCMA) coefficient (b), i.e., K_i > 2-3 mJ/m² and b > 1000 fJ/(Vm), are needed. In order to achieve such a large VCMA effect, exploring the origin of the VCMA effect using ideal PMA heterostructures without any interfacial defects appears to be indispensable. Recently, large PMA energies were reported in lattice-matched Fe/MgAl₂O₄ [2] and Co₂FeAl/MgAl₂O₄ heterostructures [3]. In this study, we focused on the ultrathin Fe/MgAl₂O₄(001) epitaxial interfaces to achieve high K_i and b. 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.