# Negative spin polarization and effect of composition on the atomic order and electronic structure of Mn 2 VAl Heusler alloy thin films https://mdr.nims.go.jp/datasets/166ce7b7-1206-4056-9203-6c08c5e10d67 ## File - [20241126_RDE_manuscript_MVA_CPP-GMR.pdf](https://mdr.nims.go.jp/filesets/115db015-ab7e-4b38-8239-f538f5f91acb/download) ([Detail](https://mdr.nims.go.jp/filesets/115db015-ab7e-4b38-8239-f538f5f91acb.md)) ## Id 166ce7b7-1206-4056-9203-6c08c5e10d67 ## Local identifier ## Visibility open_to_public ## State published ## Created at 2024-11-26T06:08:11.900121Z ## Updated at 2024-12-25T07:31:08.214547Z ## Published at 2024-12-25T07:31:08.277229Z ## Doi https://doi.org/10.48505/nims.5224 ## First published url https://doi.org/10.1103/physrevmaterials.8.114408 ## Date published 2024-11-12 ## Recorded date published 2024-11 ## Resource type journal_article ## Manuscript type accepted_manuscript ## Collection ## Title - title: Negative spin polarization and effect of composition on the atomic order and electronic structure of Mn2VAl Heusler alloy thin films title_type: original lang: en ## Description - description: " Magnetic materials with high negative spin polarization can increase design freedom of spintronic devices for high-performance operations. We studied Mn2VAl (MVA) Heusler alloy thin films to investigate the potential for negative spin polarization materials from the viewpoints of electronic structure, composition tuning, and spin injection in current-perpendicular-to-plane giant magnetoresistance (CPP-GMR) devices. Density-of-states calculations showed that MVA has a gap in the majority-spin band at the Fermi energy, leading to negative spin polarization, which is higher in the L21-ordered state than in the B2-ordered state. VMn antisites (V atoms occupying Mn sites) introduce an in-gap state detrimental to the negative spin polarization, whereas MnV and AlV antisites exhibit a smaller impact, preserving the gap. High-quality MVA films were fabricated by sputter-deposition at elevated temperatures, achieving the B2 and L21 order parameters of 0.88 and 0.5 at 600 °C, respectively. The comparison of stoichiometric and various off-stoichiometric samples revealed that Mn-rich and Al-rich compositions exhibited improved ordering and reduced detrimental VMn antisites. The advantage of these off-stoichiometric compositions was demonstrated by the negative magnetoresistance measured in the epitaxial CPP-GMR devices consisting of MVA/Ag spacer/CoFe. The devices with Mn2.2V0.6Al1.2 exhibited a very large negative magnetoresistance of −4.4%, indicating high negative spin polarization of MVA. In addition, highly efficient spin-transfer torque generation via the spin injection from MVA was demonstrated with the opposite torque direction to that from the conventional positive spin polarization materials, paving the way for a new class of spintronic devices. " description_type: abstract lang: und ## Creator - name: Hirofumi Suto role: author orcid: https://orcid.org/0000-0003-4387-5862 organization: National Institute for Materials Science ror: https://ror.org/026v1ze26 - name: Vineet Barwal role: author orcid: https://orcid.org/0000-0001-9445-5900 - 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: Kodchakorn Simalaotao role: author orcid: https://orcid.org/0000-0002-6098-4422 organization: National Institute for Materials Science ror: https://ror.org/026v1ze26 - name: Taisuke Sasaki role: author orcid: https://orcid.org/0000-0002-5952-7638 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: Hiroo Tajiri role: author - name: Loku Singgappulige Rosantha Kumara role: author orcid: https://orcid.org/0000-0001-9160-6590 - name: Tomoyuki Koganezawa role: author orcid: https://orcid.org/0000-0002-9302-5025 - name: Yuya Sakuraba role: author orcid: https://orcid.org/0000-0003-4618-9550 organization: National Institute for Materials Science ror: https://ror.org/026v1ze26 ## Contact agent ## Publisher organization: American Physical Society (APS) ## Managing organization ## Keyword - subject: Negative spin polarization schema: not_defined - subject: Heusler alloy schema: not_defined - subject: Mn2VAl schema: not_defined - subject: Magnetoresistance schema: not_defined - subject: Spin-transfer torque schema: not_defined - subject: Magnetic recording schema: not_defined ## Rights - identifier: http://rightsstatements.org/vocab/InC/1.0/ ## Other identifier(s) ## Data origin - data_origin_type: other ## Embargo ## Journal - title: Physical Review Materials issn: '24759953' volume: '8' issue: '11' article_number: '114408' ## Conference ## Related item ## Funding - identifier: 21K20434 funder_name: Japan Society for the Promotion of Science - identifier: 23K03934 funder_name: Japan Society for the Promotion of Science - identifier: JPJ011438 funder_name: Ministry of Education, Culture, Sports, Science and Technology ## 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: 115db015-ab7e-4b38-8239-f538f5f91acb filename: 20241126_RDE_manuscript_MVA_CPP-GMR.pdf content_type: application/pdf size: 2538366 md5: 253461dc130fe2ae1d78085588626c91 ## Thumbnail fileset_id: 115db015-ab7e-4b38-8239-f538f5f91acb filename: 20241126_RDE_manuscript_MVA_CPP-GMR.pdf