title: Field-free switching of perpendicular magnetization through spin-orbit torque in antiferromagnet/ferromagnet/oxide structures.
abstract: Spin-orbit torques arising from the spin-orbit coupling of non-magnetic heavy metals allow electrical switching of perpendicular magnetization. However, the switching is not purely electrical in laterally homogeneous structures. An extra in-plane magnetic field is indeed required to achieve deterministic switching, and this is detrimental for device applications. On the other hand, if antiferromagnets can generate spin-orbit torques, they may enable all-electrical deterministic switching because the desired magnetic field may be replaced by their exchange bias. Here we report sizeable spin-orbit torques in IrMn/CoFeB/MgO structures. The antiferromagnetic IrMn layer also supplies an in-plane exchange bias field, which enables all-electrical deterministic switching of perpendicular magnetization without any assistance from an external magnetic field. Together with sizeable spin-orbit torques, these features make antiferromagnets a promising candidate for future spintronic devices. We also show that the signs of the spin-orbit torques in various IrMn-based structures cannot be explained by existing theories and thus significant theoretical progress is required.
authors.affiliation: Department of Materials Science and Engineering and KI for Nanocentury, KAIST, Daejeon 34141, Korea.
authors.forename: Young-Wan
authors.initials: YW
authors.lastname: Oh
authors.affiliation: Department of Materials Science and Engineering and KI for Nanocentury, KAIST, Daejeon 34141, Korea.|School of Electrical Engineering, KAIST, Daejeon 34141, Korea.
authors.forename: Seung-Heon
authors.initials: SH
authors.lastname: Chris Baek
authors.affiliation: Department of Materials Science and Engineering and KI for Nanocentury, KAIST, Daejeon 34141, Korea.
authors.forename: Y M
authors.initials: YM
authors.lastname: Kim
authors.affiliation: Department of Materials Science and Engineering and KI for Nanocentury, KAIST, Daejeon 34141, Korea.
authors.forename: Hae Yeon
authors.initials: HY
authors.lastname: Lee
authors.affiliation: Department of Materials Science and Engineering and KI for Nanocentury, KAIST, Daejeon 34141, Korea.
authors.forename: Kyeong-Dong
authors.initials: KD
authors.lastname: Lee
authors.affiliation: Department of Materials Science and Engineering, Korea University, Seoul 02841, Korea.|Center for Spintronics, Korea Institute of Science and Technology, Seoul 02792, Korea.
authors.forename: Chang-Geun
authors.initials: CG
authors.lastname: Yang
authors.affiliation: Center for Spintronics, Korea Institute of Science and Technology, Seoul 02792, Korea.|KU-KIST Graduate School of Converging Science and Technology, Korea University, Seoul 02841, Korea.
authors.forename: Eun-Sang
authors.initials: ES
authors.lastname: Park
authors.affiliation: Department of Materials Science and Engineering, Korea University, Seoul 02841, Korea.
authors.forename: Ki-Seung
authors.initials: KS
authors.lastname: Lee
authors.affiliation: PCTP and Department of Physics, Pohang University of Science and Technology, Pohang 37673, Korea.|Center for Nanoscale Science and Technology, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, USA.|Maryland Nanocenter, University of Maryland, College Park, Maryland 20742, USA.|Basic Science Research Institute, Pohang University of Science and Technology, Pohang 37673, Korea.
authors.forename: Kyoung-Whan
authors.identifier: 0000-0002-1382-7088
authors.initials: KW
authors.lastname: Kim
authors.affiliation: Department of Materials Science and Engineering, Korea University, Seoul 02841, Korea.
authors.forename: Gyungchoon
authors.initials: G
authors.lastname: Go
authors.affiliation: Department of Materials Science and Engineering, Graduate School of Energy Science Technology, Chungnam National University, Daejeon 34134, Korea.
authors.forename: Jong-Ryul
authors.initials: JR
authors.lastname: Jeong
authors.affiliation: Center for Spintronics, Korea Institute of Science and Technology, Seoul 02792, Korea.
authors.forename: Byoung-Chul
authors.identifier: 0000-0001-8215-3286
authors.initials: BC
authors.lastname: Min
authors.affiliation: PCTP and Department of Physics, Pohang University of Science and Technology, Pohang 37673, Korea.
authors.forename: Hyun-Woo
authors.identifier: 0000-0002-1648-8093
authors.initials: HW
authors.lastname: Lee
authors.affiliation: Department of Materials Science and Engineering, Korea University, Seoul 02841, Korea.|KU-KIST Graduate School of Converging Science and Technology, Korea University, Seoul 02841, Korea.
authors.forename: Kyung-Jin
authors.identifier: 0000-0001-6269-2266
authors.initials: KJ
authors.lastname: Lee
authors.affiliation: Department of Materials Science and Engineering and KI for Nanocentury, KAIST, Daejeon 34141, Korea.
authors.forename: Byong-Guk
authors.identifier: 0000-0001-8813-7025
authors.initials: BG
authors.lastname: Park