Recovery of half-metallicity of oxide surfaces and its application to spin injection

2013 Fiscal Year Final Research Report

• Project/Area Number: 23656034
• Research Category: Grant-in-Aid for Challenging Exploratory Research
• Allocation Type: Multi-year Fund
• Research Field: Thin film/Surface and interfacial physical properties
• Research Institution: National Institute for Materials Science
• Principal Investigator: KURAHASHI Mitsunori 独立行政法人物質・材料研究機構, 極限計測ユニット, 主席研究員 (10354359)
• Project Period (FY): 2011 – 2012
• Keywords: 表面・界面物性 / 磁性 / 酸化物

Research Abstract

Half-metallic ferromagnets are important materials in the field of spintronics, but the spin polarization at their surfaces or interfaces is usually much lower than 100%, causing the transport properties of the devices much lower than expected from the bulk spin polarization. We have previously reported that the surface spin polarization of Fe3O4(100) can be drastically improved by hydrogen termination. In this study, we analyzed this phenomena for an Fe3O4(111) surface and tried to utilize it for inducing high spin polarization to adsorbed molecules. We clarified that the spin polarization at the (111) surface is positive unexpectedly and is not improved by H termination. This would originate from the fact that the tetrahedrally-cordinated Fe terminates the (111) surface.

Research Products

• [Journal Article] Significant variation of surface spin polarization through group IV atom (C Si Ge Sn) adsorption on Fe_3O_4(100) (2014)
  • Author(s): X. Sun, S. D. Li, B. Wang, M. Kurahashi, A. Pratt, Y . Yamauchi
  • Journal Title: Phys. Chem. Chem. Phys Volume: 16[1] Pages: 95-102
  • Peer Reviewed
• [Journal Article] Spin polarization of single-layer graphene epitaxially grown on Ni(111) thin film (2013)
  • Author(s): S. Entani, M. Kurahashi, X. Sun, Y. Yamauchi
  • Journal Title: Carbon Volume: 61 Pages: 134-139
  • Peer Reviewed
• [Journal Article] Spin polarization study of graphene on the Ni(111) surface by density functional theory calculations with a semiempirical long-range dispersion correction (2013)
  • Author(s): X. Sun, S Entani, Y . Yamauchi, A. Pratt, M. Kurahashi
  • Journal Title: J. Appl. Phys Volume: 114[14] Pages: 143713
  • Peer Reviewed
• [Journal Article] Energy-level alignment at the Alq3/Fe_3O_4(001) interface (2012)
  • Author(s): A. Pratt, L. Dunne, X. Sun, M. Kurahashi and Y . Yamauchi
  • Journal Title: J. Appl. Phys Volume: 111[7] Pages: 07C114
  • Peer Reviewed
• [Journal Article] Direct observation of a positive spin polarization at the (111) surface of magnetite (2012)
  • Author(s): A. Pratt, M. Kurahashi, X. Sun, D. Gilks and Y . Yamauchi
  • Journal Title: Phys. Rev. B Volume: 85 Pages: 180409
  • Peer Reviewed
• [Journal Article] Magnetic properties of O_2 adsorbed on Cu(100) : A spin-polarized metastable He beam study (2012)
  • Author(s): M. Kurahashi, X. Sun, Y . Yamauchi
  • Journal Title: Phys. Rev . B Volume: 86[24] Pages: 245421
  • Peer Reviewed
• [Presentation] Advances in the use of a spin-polarized metastable helium beam to characterize surface magnetic properties (2014)
  • Author(s): A. Pratt, M. Kurahashi, Xia Sun, Y . Yamauchi
  • Organizer: 20th International Workshop on Inelastic Ion-Surface Collisions
  • Place of Presentation: Adelaide
  • Year and Date: 20140216-21
• [Presentation] 磁性体に接する単層グラフェンのスピン偏極 (2013)
  • Author(s): 孫霞, 圓谷志郎, 倉橋光紀, 山内泰
  • Organizer: 2013年真空・表面科学合同講演会
  • Place of Presentation: つくば
  • Year and Date: 20131126-28
• [Presentation] 有機半導体/酸化物界面における分子配向の温度依存性 (2013)
  • Author(s): Andrew Pratt, Y u Jeong Bae, Xia Sun, 倉橋光紀, Nyun Jong Lee, T ae Hee Kim, 山内泰
  • Organizer: Japan Society of Applied Physics Autumn Meeting
  • Place of Presentation: 同志社大学
  • Year and Date: 20130916-19
• [Presentation] Tailoring surface properties for molecular spintronics (2013)
  • Author(s): A. Pratt, M. Kurahashi, Xia Sun, Y . Yamauchi
  • Organizer: JSPS York-Tohoku Symposium on Spintronics
  • Place of Presentation: York
  • Year and Date: 20130610-12
• [Presentation] Tailoring surface properties for molecular spintronics (2013)
  • Author(s): A. Pratt, M.Kurahashi, Y . Yamauchi
  • Organizer: Invited seminar at EWHA University Seoul Korea
  • Place of Presentation: Seoul
  • Year and Date: 2013-05-13
• [Presentation] Tailoring the spin polarization at the surface of Fe_3O_4 (2012)
  • Author(s): A. Pratt, M. Kurahashi, X. Sun, Y . Yamauchi
  • Organizer: IUMRS-International Conference on Electronic Materials
  • Place of Presentation: Yokohama
  • Year and Date: 20120923-28
• [Presentation] A spin-polarized metastable helium beam for organic spintronics (2012)
  • Author(s): A. Pratt, M. Kurahashi, X. Sun, Y . Y amauchi
  • Organizer: 4th International Meeting on Spins in Organic Semiconductors
  • Place of Presentation: London
  • Year and Date: 20120910-13
• [Presentation] Intrinsic spin polarity at the magnetite Fe_3O_4 surface (2012)
  • Author(s): A. Pratt, M. Kurahashi, X. Sun, Y . Yamauchi
  • Organizer: The 24th conference of the EPS condensed matter division
  • Place of Presentation: Edinburgh
  • Year and Date: 20120902-07
• [Presentation] Direct evidence for positive spin polarization at the Fe_3O_4(111) surface (2012)
  • Author(s): A. Pratt, 倉橋光紀 , 孫霞 , 山内泰
  • Organizer: 日本物理学会年次大会
  • Place of Presentation: 神戸
  • Year and Date: 20120324-27
• [Remarks]
  • URL: http://samurai.nims.go.jp/KURAHASHI_Mitsunori-j.html
• [Patent(Industrial Property Rights)] オゾンビーム発生装置 (2012)
  • Inventor(s): 山内泰, プラットアンドリュー, 倉橋光紀
  • Industrial Property Rights Holder: 物質・材料研究機構
  • Industrial Property Rights Type: 特許特開2013-256398号
  • Patent Publication Number: 特開2013-256398号
  • Filing Date: 2012-06-12