Magnetization control for bit pattern formation of spinel ferromagnetic oxides by Kr ion implantation
Author(s) -
Eiji Kita,
Kazuya Suzuki,
Yang Liu,
Yuji Utsumi,
Jumpei Morishita,
Daiki Oshima,
Takeshi Kato,
Tomohiko Niizeki,
Ko Mibu,
Hideto Yanagihara
Publication year - 2014
Publication title -
journal of applied physics
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.699
H-Index - 319
eISSN - 1089-7550
pISSN - 0021-8979
DOI - 10.1063/1.4868704
Subject(s) - ferromagnetism , magnetization , spinel , ion implantation , ion , materials science , paramagnetism , condensed matter physics , oxide , magnetism , irradiation , spontaneous magnetization , chemistry , metallurgy , physics , magnetic field , organic chemistry , quantum mechanics , nuclear physics
As a first step toward the development of bit-patterned magnetic media made of oxides, we investigated the effectiveness of magnetism control by Kr implantation in a typical spinel ferromagnetic oxide, Fe3O4. We implanted Kr ions accelerated at 30 kV on 13-nm-thick Fe3O4 thin films at dosages of (1–40) × 1014 ions/cm2. Magnetization decreased with increase in ion dosages and disappeared when irradiation was greater than 2 × 1015 ions/cm2 of Kr ions. These dosages are more than ten times smaller than that used in the N2 implantation for metallic and oxide ferromagnets. Both the temperature dependence of magnetization and the Mössbauer study suggest that the transition of Fe3O4 from ferromagnetic to paramagnetic took place sharply due to Kr ion irradiation, which produces two-phase separation—ferromagnetic and nonmagnetic with insufficient dosage of Kr ions
Accelerating Research
Robert Robinson Avenue,
Oxford Science Park, Oxford
OX4 4GP, United Kingdom
Address
John Eccles HouseRobert Robinson Avenue,
Oxford Science Park, Oxford
OX4 4GP, United Kingdom