# Nano-crystal domains in Co-based fcc(111) epitaxial magnetic junctions and their impact on tunnel magnetoresistance https://mdr.nims.go.jp/datasets/eac10ea0-5385-42cb-99b5-5d43454a7a47 ## File - [Accepted manuscript.pdf](https://mdr.nims.go.jp/filesets/43376ee1-56be-43dd-bd37-313c51a5f692/download) ([Detail](https://mdr.nims.go.jp/filesets/43376ee1-56be-43dd-bd37-313c51a5f692.md)) ## Id eac10ea0-5385-42cb-99b5-5d43454a7a47 ## Local identifier ## Visibility open_to_public ## State published ## Created at 2023-12-26T05:14:08.857253Z ## Updated at 2025-10-21T07:16:53.908009Z ## Published at 2025-10-21T07:16:02.634621Z ## Doi https://doi.org/10.48505/nims.4752 ## First published url https://doi.org/10.1016/j.actamat.2023.119394 ## Date published 2023-09-27 ## Recorded date published 2023-12 ## Resource type journal_article ## Manuscript type accepted_manuscript ## Collection ## Title - title: Nano-crystal domains in Co-based fcc(111) epitaxial magnetic junctions and their impact on tunnel magnetoresistance title_type: original lang: en ## Description - description: Nano-crystal domain structures formed in a MgO barrier and their effects on tunnel magnetoresistance (TMR) in epitaxial fcc-Co90Fe10 (CoFe)(111)/MgO(111)/CoFe(111) magnetic tunnel junctions (MTJs) have been systematically studied using scanning transmission electron microscopy and first-principles calculations. These domains are widely distributed in the (111)-textured MgO layer, being different from conventional bcc-CoFe/MgO(001)-based MTJs. The (111)-texture is formed by extension of {111} planes through several adjacent MgO domains. Three types of orientation relationships (ORs) between CoFe and MgO are identified, including cube-on-cube type (Type-1), twin-like type (Type-2), and unexpected type (Type-3). Crystallographic analysis indicated that Type-2 OR is a variant of Type-1 OR, triggered by different stacking orders of MgO(111) planes, while Type-3 OR is formed by a 30◦ in-plane rotation of MgO lattice relative to Type-1 OR. Due to the large in-plane lattice mismatch (19.6%) between Co(111) and MgO(111) in Type-1 and Type-2 ORs, Type-3 OR (mismatch 3.4%) can be stabilized. First-principles calculations uncovered that the theoretical TMR ratio of the MgO(111) MTJ with Type-3 OR is ~2 orders of magnitude smaller than that with Type-1 and Type-2 ORs. The small contribution of Type-3 OR to the transport reasonably interprets why the experimental TMR ratio (~37%) is much lower than the theoretical value (~2100%) in the Co/MgO/Co(111) MTJ. This study has revealed the nano-crystal domain formation unique to the fcc-CoFe/MgO(111) MTJs, indicating that controlling the nano-crystal domains (e.g., lattice optimization by atomic doping) can be a guiding principle to develop MgO(111)-based epitaxial MTJs and related heterostructure devices. description_type: abstract lang: eng ## Creator - name: Cong He role: author organization: National Institute for Materials Science ror: https://ror.org/026v1ze26 - name: Keisuke Masuda role: author orcid: https://orcid.org/0000-0002-6884-6390 organization: National Institute for Materials Science ror: https://ror.org/026v1ze26 - name: Jieyuan Song role: author orcid: https://orcid.org/0000-0001-6846-2875 organization: National Institute for Materials Science ror: https://ror.org/026v1ze26 - name: Thomas Scheike role: author orcid: https://orcid.org/0000-0002-9163-5524 organization: National Institute for Materials Science ror: https://ror.org/026v1ze26 - name: Zhenchao Wen role: author orcid: https://orcid.org/0000-0001-7496-1339 organization: National Institute for Materials Science ror: https://ror.org/026v1ze26 - name: Yoshio Miura role: author orcid: https://orcid.org/0000-0002-5605-5452 organization: National Institute for Materials Science ror: https://ror.org/026v1ze26 - name: Tadakatsu Ohkubo role: author orcid: https://orcid.org/0000-0003-3548-1951 organization: National Institute for Materials Science ror: https://ror.org/026v1ze26 - name: Kazuhiro Hono role: author orcid: https://orcid.org/0000-0001-7367-0193 organization: National Institute for Materials Science ror: https://ror.org/026v1ze26 - name: Seiji Mitani role: author orcid: https://orcid.org/0000-0002-1348-0774 organization: National Institute for Materials Science ror: https://ror.org/026v1ze26 - name: Hiroaki Sukegawa role: author orcid: https://orcid.org/0000-0002-4034-7848 organization: National Institute for Materials Science ror: https://ror.org/026v1ze26 ## Contact agent ## Publisher organization: Elsevier BV ## Managing organization ## Keyword - subject: Spintronics schema: not_defined - subject: Magnetic tunnel junctions schema: not_defined - subject: Tunnel magnetoresistance schema: not_defined - subject: Epitaxial growth schema: not_defined ## Rights - identifier: https://creativecommons.org/licenses/by-nc-nd/4.0/ ## Other identifier(s) ## Data origin - data_origin_type: other ## Embargo start_date: 2023-09-28 end_date: 2025-09-28 ## Journal - title: Acta Materialia issn: '13596454' volume: '261' article_number: '119394' ## Conference ## Related item ## Funding - identifier: 20K14782 funder_name: Japan Society for the Promotion of Science - identifier: 22H04966 funder_name: Japan Society for the Promotion of Science - identifier: 23K03933 funder_name: Japan Society for the Promotion of Science - funder_name: Core Research for Evolutional Science and Technology - identifier: JPMJCR19J4 funder_name: Japan Science and Technology Agency Strategic Basic Research Programs CREST - identifier: 21H01750 funder_name: Japan Society for the Promotion of Science ## Instrument ## Instrument operator ## Instrument managing organization ## Measurement method ## Specimen ## Chemical composition ## Structure for specimen ## Structural feature for specimen ## Specific property for specimen ## Process for specimen treatment ## Computational method ## Energy level/transition state ## Software ## Custom property ## Fileset - id: 43376ee1-56be-43dd-bd37-313c51a5f692 filename: Accepted manuscript.pdf content_type: application/pdf size: 2748939 md5: e1c0f843d75328ddf9fa35cf135bb551 ## Thumbnail fileset_id: 43376ee1-56be-43dd-bd37-313c51a5f692 filename: Accepted manuscript.pdf