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Title: Magnetoresistance effect in Fe{sub 20}Ni{sub 80}/graphene/Fe{sub 20}Ni{sub 80} vertical spin valves

Abstract

Vertical spin valve devices with junctions of single- and bi-layer graphene interlayers sandwiched with Fe{sub 20}Ni{sub 80} (Permalloy) electrodes were fabricated by exploiting the direct growth of graphene on the Permalloy. The linear current-voltage characteristics indicated that ohmic contacts were realized at the interfaces. The systematic characterization revealed the significant modification of the electronic state of the interfacial graphene layer on the Permalloy surface, which indicates the strong interactions at the interface. The ohmic transport was attributable to the strong interface-interaction. The vertical resistivity of the graphene interlayer and the spin asymmetry coefficient at the graphene/Permalloy interface were obtained to be 0.13 Ω cm and 0.06, respectively. It was found that the strong interface interaction modifies the electronic structure and metallic properties in the vertical spin valve devices with bi-layer graphene as well as single-layer graphene.

Authors:
; ;  [1]; ; ;  [2];  [2];  [3];  [1];  [3]
  1. Quantum Beam Science Directorate, National Institutes for Quantum and Radiological Science and Technology, 2-4 Shirakata-Shirane, Tokai, Ibaraki 319-1195 (Japan)
  2. Institute for Materials Research, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577 (Japan)
  3. (Japan)
Publication Date:
OSTI Identifier:
22590484
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 109; Journal Issue: 8; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; ASYMMETRY COEFFICIENTS; CONNECTORS; ELECTRIC POTENTIAL; ELECTRONIC STRUCTURE; GRAPHENE; INTERFACES; LAYERS; MAGNETORESISTANCE; PERMALLOY; SPIN

Citation Formats

Entani, Shiro, E-mail: entani.shiro@qst.go.jp, Naramoto, Hiroshi, Sakai, Seiji, Seki, Takeshi, Yamamoto, Tatsuya, Takahashi, Saburo, Sakuraba, Yuya, National Institute for Materials Science, 1-2-1 Sengen, Tsukuba 305-004, Takanashi, Koki, and Institute for Materials Research, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577. Magnetoresistance effect in Fe{sub 20}Ni{sub 80}/graphene/Fe{sub 20}Ni{sub 80} vertical spin valves. United States: N. p., 2016. Web. doi:10.1063/1.4961669.
Entani, Shiro, E-mail: entani.shiro@qst.go.jp, Naramoto, Hiroshi, Sakai, Seiji, Seki, Takeshi, Yamamoto, Tatsuya, Takahashi, Saburo, Sakuraba, Yuya, National Institute for Materials Science, 1-2-1 Sengen, Tsukuba 305-004, Takanashi, Koki, & Institute for Materials Research, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577. Magnetoresistance effect in Fe{sub 20}Ni{sub 80}/graphene/Fe{sub 20}Ni{sub 80} vertical spin valves. United States. doi:10.1063/1.4961669.
Entani, Shiro, E-mail: entani.shiro@qst.go.jp, Naramoto, Hiroshi, Sakai, Seiji, Seki, Takeshi, Yamamoto, Tatsuya, Takahashi, Saburo, Sakuraba, Yuya, National Institute for Materials Science, 1-2-1 Sengen, Tsukuba 305-004, Takanashi, Koki, and Institute for Materials Research, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577. 2016. "Magnetoresistance effect in Fe{sub 20}Ni{sub 80}/graphene/Fe{sub 20}Ni{sub 80} vertical spin valves". United States. doi:10.1063/1.4961669.
@article{osti_22590484,
title = {Magnetoresistance effect in Fe{sub 20}Ni{sub 80}/graphene/Fe{sub 20}Ni{sub 80} vertical spin valves},
author = {Entani, Shiro, E-mail: entani.shiro@qst.go.jp and Naramoto, Hiroshi and Sakai, Seiji and Seki, Takeshi and Yamamoto, Tatsuya and Takahashi, Saburo and Sakuraba, Yuya and National Institute for Materials Science, 1-2-1 Sengen, Tsukuba 305-004 and Takanashi, Koki and Institute for Materials Research, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577},
abstractNote = {Vertical spin valve devices with junctions of single- and bi-layer graphene interlayers sandwiched with Fe{sub 20}Ni{sub 80} (Permalloy) electrodes were fabricated by exploiting the direct growth of graphene on the Permalloy. The linear current-voltage characteristics indicated that ohmic contacts were realized at the interfaces. The systematic characterization revealed the significant modification of the electronic state of the interfacial graphene layer on the Permalloy surface, which indicates the strong interactions at the interface. The ohmic transport was attributable to the strong interface-interaction. The vertical resistivity of the graphene interlayer and the spin asymmetry coefficient at the graphene/Permalloy interface were obtained to be 0.13 Ω cm and 0.06, respectively. It was found that the strong interface interaction modifies the electronic structure and metallic properties in the vertical spin valve devices with bi-layer graphene as well as single-layer graphene.},
doi = {10.1063/1.4961669},
journal = {Applied Physics Letters},
number = 8,
volume = 109,
place = {United States},
year = 2016,
month = 8
}
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