title: Multimetal-Substituted Epsilon-Iron Oxide ϵ-Ga0.31 Ti0.05 Co0.05 Fe1.59 O3 for Next-Generation Magnetic Recording Tape in the Big-Data Era.
abstract: From the viewpoints of large capacity, long-term guarantee, and low cost, interest in magnetic recording tapes has undergone a revival as an archive storage media for big data. Herein, we prepared a new series of metal-substituted ϵ-Fe2 O3 , ϵ-Ga(III) 0.31 Ti(IV) 0.05 Co(II) 0.05 Fe(III) 1.59 O3 , nanoparticles with an average size of 18 nm. Ga, Ti, and Co cations tune the magnetic properties of ϵ-Fe2 O3 to the specifications demanded for a magnetic recording tape. The coercive field was tuned to 2.7 kOe by introduction of single-ion anisotropy on Co(II) (S=3/2) along the c-axis. The saturation magnetization was increased by 44 % with Ga(III) (S=0) and Ti(IV) (S=0) substitution through the enhancement of positive sublattice magnetizations. The magnetic tape media was fabricated using an actual production line and showed a very sharp signal response and a remarkably high signal-to-noise ratio compared to the currently used magnetic tape.
authors.affiliation: Department of Chemistry, School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan. ohkoshi@chem.s.u-tokyo.ac.jp.
authors.forename: Shin-Ichi
authors.initials: S
authors.lastname: Ohkoshi
authors.affiliation: Department of Chemistry, School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan.
authors.forename: Asuka
authors.initials: A
authors.lastname: Namai
authors.affiliation: Department of Chemistry, School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan.
authors.forename: Marie
authors.initials: M
authors.lastname: Yoshikiyo
authors.affiliation: Department of Chemistry, School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan.
authors.forename: Kenta
authors.initials: K
authors.lastname: Imoto
authors.affiliation: TDK Corporation, 2-15-7 Higashi-owada, Ichikawa, Chiba, 272-8558, Japan.
authors.forename: Kazunori
authors.initials: K
authors.lastname: Tamazaki
authors.affiliation: TDK Corporation, 2-15-7 Higashi-owada, Ichikawa, Chiba, 272-8558, Japan.
authors.forename: Koji
authors.initials: K
authors.lastname: Matsuno
authors.affiliation: TDK Corporation, 2-15-7 Higashi-owada, Ichikawa, Chiba, 272-8558, Japan.
authors.forename: Osamu
authors.initials: O
authors.lastname: Inoue
authors.affiliation: TDK Corporation, 2-15-7 Higashi-owada, Ichikawa, Chiba, 272-8558, Japan.
authors.forename: Tsutomu
authors.initials: T
authors.lastname: Ide
authors.affiliation: Dowa Electronics Materials. Co.,Ltd., 1-3-1 Kaigandori, Minami-ku, Okayama, 702-8506, Japan.
authors.forename: Kenji
authors.initials: K
authors.lastname: Masada
authors.affiliation: Dowa Electronics Materials. Co.,Ltd., 1-3-1 Kaigandori, Minami-ku, Okayama, 702-8506, Japan.
authors.forename: Masahiro
authors.initials: M
authors.lastname: Goto
authors.affiliation: Dowa Electronics Materials. Co.,Ltd., 1-3-1 Kaigandori, Minami-ku, Okayama, 702-8506, Japan.
authors.forename: Takashi
authors.initials: T
authors.lastname: Goto
authors.affiliation: Dowa Electronics Materials. Co.,Ltd., 1-3-1 Kaigandori, Minami-ku, Okayama, 702-8506, Japan.
authors.forename: Takayuki
authors.initials: T
authors.lastname: Yoshida
authors.affiliation: Dowa Electronics Materials. Co.,Ltd., 1-3-1 Kaigandori, Minami-ku, Okayama, 702-8506, Japan.
authors.forename: Tatsuro
authors.initials: T
authors.lastname: Miyazaki
keywords: epsilon-iron oxide; hard magnetic ferrite; iron; magnetic properties; magnetic recording tape; nanoparticles