Perpendicular magnetic clusters with configurable domain structures via dipole–dipole interactions
perpendicular anisotropy, dipole–dipole interaction, multistate magnetic recording, logic device, magnetic domino
ABSTRACT Magnetic single-domain islands based on in-plane anisotropy (usually, shape anisotropy) and their dipole–dipole interactions have been investigated extensively in recent years. This has been driven by potential applications in magnetic recording, spintronics, magneto-biology, etc. Here, we propose a concept of outof- plane magnetic clusters with configurable domain structures (multi-flux states) via dipole–dipole interactions. Their flux stages can be switched through an external magnetic field. The concept has been successfully demonstrated by patterned [Co/Pd] islands. A [Co/Pd] multilayer exhibits a large perpendicular anisotropy, a strong physical separation, and uniform intrinsic properties after being patterned into individual islands by electron beam lithography. A threeisland cluster with six stable flux states has been realized by optimizing island size, thickness, gap, anisotropy, saturation magnetization, etc. Using [Co/Pd] multilayers, we have optimized the island structure by tuning magnetic properties (saturation magnetization and perpendicular anisotropy) using Landau–Liftshitz– Gilbert (LLG) simulation/calculation. Potential applications have been proposed, including a flexi-programmable logic device with AND, OR, NAND, and NOR functionalities and a magnetic domino, which can propagate magnetic current as far as 1 μm down from the surface via vertical dipole–dipole interactions.
Tsinghua University Press
Weimin Li,Seng Kai Wong,Tun Seng Herng,Lee Koon Yap,Cheow Hin Sim,Zhengchun Yang,Yunjie Chen,Jianzhong Shi,Guchang Han,Junmin Xue,Jun Ding, Perpendicular magnetic clusters with configurable domain structures via dipole–dipole interactions. NanoRes.null