{"title":"Ferrimagnetic and Metallic Properties of (001) NiCo₂O₄ Films Fabricated at Various Oxygen Pressures","authors":"Jungbae Kim, Yeon Jung Park, J. Dho","doi":"10.4283/jmag.2023.28.2.102","DOIUrl":null,"url":null,"abstract":"Epitaxial (001) NiCo 2 O 4 films with perpendicular magnetic anisotropy were grown on (001) MgAl 2 O 4 at various oxygen pressures of 10-200 mTorr using pulsed laser deposition. X-ray diffraction suggested that the lattice constant, crystallinity, and deposition rate displayed distinctive changes around 50 mTorr. The temperature-dependent resistance displayed an insulating behavior in the films grown below 15 mTorr but a metallic one in the films grown above 20 mTorr. Magneto-optical Kerr effect measurement suggested that the NiCo 2 O 4 films grown above 15 mTorr are ferrimagnetic at room temperature and possess a distinctive perpendicular magnetic anisotropy. The ferrimagnetic-to-paramagnetic transition temperature reached a maximum of ~385 K at 50 mTorr. During the magnetic reversal, the density of small nucleated domains increased with increasing oxygen pressure from 20 to 200 mTorr, and exhibited metallic ferrimagnetism at room temperature. Consequently, the optimal growth condition for magnetic device applications of NiCo 2 O 4 films is believed to be 50-200 mTorr at 320 ℃.","PeriodicalId":16147,"journal":{"name":"Journal of Magnetics","volume":null,"pages":null},"PeriodicalIF":0.6000,"publicationDate":"2023-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of Magnetics","FirstCategoryId":"88","ListUrlMain":"https://doi.org/10.4283/jmag.2023.28.2.102","RegionNum":4,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q4","JCRName":"MATERIALS SCIENCE, MULTIDISCIPLINARY","Score":null,"Total":0}
引用次数: 0
Abstract
Epitaxial (001) NiCo 2 O 4 films with perpendicular magnetic anisotropy were grown on (001) MgAl 2 O 4 at various oxygen pressures of 10-200 mTorr using pulsed laser deposition. X-ray diffraction suggested that the lattice constant, crystallinity, and deposition rate displayed distinctive changes around 50 mTorr. The temperature-dependent resistance displayed an insulating behavior in the films grown below 15 mTorr but a metallic one in the films grown above 20 mTorr. Magneto-optical Kerr effect measurement suggested that the NiCo 2 O 4 films grown above 15 mTorr are ferrimagnetic at room temperature and possess a distinctive perpendicular magnetic anisotropy. The ferrimagnetic-to-paramagnetic transition temperature reached a maximum of ~385 K at 50 mTorr. During the magnetic reversal, the density of small nucleated domains increased with increasing oxygen pressure from 20 to 200 mTorr, and exhibited metallic ferrimagnetism at room temperature. Consequently, the optimal growth condition for magnetic device applications of NiCo 2 O 4 films is believed to be 50-200 mTorr at 320 ℃.
期刊介绍:
The JOURNAL OF MAGNETICS provides a forum for the discussion of original papers covering the magnetic theory, magnetic materials and their properties, magnetic recording materials and technology, spin electronics, and measurements and applications. The journal covers research papers, review letters, and notes.