title: Magnetization amplified by structural disorder within nanometre-scale interface region.
abstract: Direct magnetization measurements from narrow, complex-shaped antiphase boundaries (APBs; that is, planar defect produced in any ordered crystals) are vitally important for advances in materials science and engineering. However, in-depth examination of APBs has been hampered by the lack of experimental tools. Here, based on electron microscopy observations, we report the unusual relationship between APBs and ferromagnetic spin order in Fe70Al30. Thermally induced APBs show a finite width (2-3 nm), within which significant atomic disordering occurs. Electron holography studies revealed an unexpectedly large magnetic flux density at the APBs, amplified by approximately 60% (at 293 K) compared with the matrix value. At elevated temperatures, the specimens showed a peculiar spin texture wherein the ferromagnetic phase was confined within the APB region. These observations demonstrate ferromagnetism stabilized by structural disorder within APBs, which is in direct contrast to the traditional understanding. The results accordingly provide rich conceptual insights for engineering APB-induced phenomena.
authors.affiliation: 1] Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, Sendai 980-8577, Japan [2] Center for Emergent Matter Science, RIKEN, Wako 351-0198, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Murakami
authors.affiliation: 1] Center for Emergent Matter Science, RIKEN, Wako 351-0198, Japan [2] Department of Materials Science, Tohoku University, Sendai 980-8579, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Niitsu
authors.affiliation: 1] Center for Emergent Matter Science, RIKEN, Wako 351-0198, Japan [2] Central Research Laboratory, Hitachi Ltd., Hatoyama 350-0395, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Tanigaki
authors.affiliation: Department of Materials Science, Tohoku University, Sendai 980-8579, Japan.
authors.forename: R
authors.initials: R
authors.lastname: Kainuma
authors.affiliation: 1] Center for Emergent Matter Science, RIKEN, Wako 351-0198, Japan [2] Department of Materials Science and Engineering, Dong-A University, Busan 604-714, Republic of Korea.
authors.forename: H S
authors.initials: HS
authors.lastname: Park
authors.affiliation: 1] Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, Sendai 980-8577, Japan [2] Center for Emergent Matter Science, RIKEN, Wako 351-0198, Japan.
authors.forename: D
authors.initials: D
authors.lastname: Shindo