講演情報
[11a-E208-1]Evaluation of the critical current density and magnetization dynamics of SOT Switching in Co/Gd Multilayer
〇Shoko Yoshida1, Dongchan Jeong1, Tetsuma Mandokoro1, Yoichi Shiota1,2, Hisakazu Matsuki1,2, Ryusuke Hisatomi1,2, Shutaro Karube1,2, Teruo Ono1,2,3 (1.ICR, Kyoto Univ., 2.CSRN, Kyoto Univ., 3.SRIS, Tohoku Univ)
キーワード：
Spin-Orbit torque switching、magnetic memory、ferrimagnetism
Domain wall motion memory is a promising candidate for next-generation memory owing to its high storage density and nonvolatile characteristics. Our recently proposed vertical domain-wall motion memory has been shown by simulations to achieve both low critical current density and high thermal stability through optimization of the layer parameters. In this study, we investigate ferrimagnetic Co/Gd multilayers to achieve faster operation and enhance writing efficiency through spin-orbit torque (SOT).
Co/Gd multilayers with the structure Si/SiO2//Ta(5)/Pt(10)/[Co(0.2)/Gd(x)]n/Co(0.2)/Cu(3)/Ta(5)/Pt(2) (thicknesses in nm, x = 0.5–0.7, n = 1–4) were fabricated, and their magnetic properties were systematically investigated. Among these samples, the Co/Gd multilayer with x = 0.7 and n = 3 was patterned into a pillar-shaped 1-bit device. SOT switching was successfully achieved at a lower current density than that of a ferromagnetic Co reference device.
Co/Gd multilayers with the structure Si/SiO2//Ta(5)/Pt(10)/[Co(0.2)/Gd(x)]n/Co(0.2)/Cu(3)/Ta(5)/Pt(2) (thicknesses in nm, x = 0.5–0.7, n = 1–4) were fabricated, and their magnetic properties were systematically investigated. Among these samples, the Co/Gd multilayer with x = 0.7 and n = 3 was patterned into a pillar-shaped 1-bit device. SOT switching was successfully achieved at a lower current density than that of a ferromagnetic Co reference device.