title: Two-barrier stability that allows low-power operation in current-induced domain-wall motion.
abstract: Energy barriers in magnetization reversal dynamics have long been of interest because the barrier height determines the thermal stability of devices as well as the threshold force triggering their dynamics. Especially in memory and logic applications, there is a dilemma between the thermal stability of bit data and the operation power of devices, because larger energy barriers for higher thermal stability inevitably lead to larger magnetic fields (or currents) for operation. Here we show that this is not the case for current-induced magnetic domain-wall motion induced by adiabatic spin-transfer torque. By quantifying domain-wall depinning energy barriers by magnetic field and current, we find that there exist two different pinning barriers, extrinsic and intrinsic energy barriers, which govern the thermal stability and threshold current, respectively. This unique two-barrier system allows low-power operation with high thermal stability, which is impossible in conventional single-barrier systems.
authors.affiliation: Institute for Chemical Research, Kyoto University, Gokasho, Uji, Kyoto 611-0011, Japan.
authors.forename: Kab-Jin
authors.initials: KJ
authors.lastname: Kim
authors.forename: Ryo
authors.initials: R
authors.lastname: Hiramatsu
authors.forename: Tomohiro
authors.initials: T
authors.lastname: Koyama
authors.forename: Kohei
authors.initials: K
authors.lastname: Ueda
authors.forename: Yoko
authors.initials: Y
authors.lastname: Yoshimura
authors.forename: Daichi
authors.initials: D
authors.lastname: Chiba
authors.forename: Kensuke
authors.initials: K
authors.lastname: Kobayashi
authors.forename: Yoshinobu
authors.initials: Y
authors.lastname: Nakatani
authors.forename: Shunsuke
authors.initials: S
authors.lastname: Fukami
authors.forename: Michihiko
authors.initials: M
authors.lastname: Yamanouchi
authors.forename: Hideo
authors.initials: H
authors.lastname: Ohno
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Kohno
authors.forename: Gen
authors.initials: G
authors.lastname: Tatara
authors.forename: Teruo
authors.initials: T
authors.lastname: Ono