Microstructure analysis of the materials with high spin polarization and spin polarization measurement

2009 Fiscal Year Self-evaluation Report

• Project Area: Creation and control of spin current
• Project/Area Number: 19048029
• Research Category: Grant-in-Aid for Scientific Research on Priority Areas
• Allocation Type: Single-year Grants
• Review Section: Science and Engineering
• Research Institution: National Institute for Materials Science
• Principal Investigator: TAKAHASHI Yukiko National Institute for Materials Science, 磁性材料センター, 主任研究員 (50421392)
• Project Period (FY): 2007 – 2010
• Keywords: ハーフメタル / スピン偏極率 / ホイスラー合金

Research Abstract

本研究では強磁性電極の物性と素子構造を詳細に解析し、トンネル型磁気抵抗(TMR),巨大磁気抵抗(GMR)素子で高いMR特性を得るための材料設計指針を提案することを目的とする。具体的には、(1)MR素子の微細構造解析による特性発現のメカニズムの解明、(2)MR素子用の強磁性電極薄膜のスピン偏極率を点接触アンドレーエフ反射(PCAR)を用いて直接測定し、同時に膜の微細構造観察を行うことにより、高スピン偏極率を示す強磁性電極材料の探索と製膜法を確立することを目的としている。

Research Products

• [Journal Article] Bulk and interfacial scatterings in current-perpendicular-to-plane giant magnetoresistance with Co2FeAl0. 5Si0. 5 Heusler alloy layers and Ag spacer (2010)
  • Author(s): T.M. Nakatani, T. Furubayashi, S. Kasai, H. Sukegawa, Y.K. Takahashi, K. Hono
  • Journal Title: Appl. Phys. Lett.
• [Journal Article] Enhanced spin polarization of Co2MnGe Heusler alloy by substitution of Ga of Ge (2010)
  • Author(s): B.S.D.C. S. Varaprasad, A. Rajanikanth, Y.K. Takahashi, K. Hono
  • Journal Title: Appl. Phys. Express 3 Pages: 023002
  • Peer Reviewed
• [Journal Article] Structural characterizations of Co2MnSi/MgO/Co2MnSi magnetic tunnel junctions by transmission electron microscopy (2010)
  • Author(s): T.M. Nakatani, Y.K. Takahashi, I. Ishikawa, M. Yamamoto, K. Hono
  • Journal Title: J. Magn. Magn. Mater. 322 Pages: 357
  • Peer Reviewed
• [Journal Article] Highly spin polarized Co2MnGa0. 5Sn0. 5 Heusler compound (2009)
  • Author(s): B. Varaprasad, A. Rajanikanth, Y.K. Takahashi, K. Hono
  • Journal Title: Acta Mater 57 Pages: 2702-2709
  • Peer Reviewed
• [Journal Article] Current-perpendicular-to-palne giant magnetoresistance of a spin valve using Co2MnSi Heusler alloy electrode (2009)
  • Author(s): K. Kodama, T. Furubayashi, H. Sukegawa, T.M. Nakatani, K. Inomata, K. Hono
  • Journal Title: J. Appl. Phys. 105 Pages: 07E905
• [Journal Article] Current-perpendicular-to-plane giant magnetoresistance in spin-valve structures using epitaxial Co2FeAl0. 5Si0. 5/Ag/Co2FeAl0. 5Si0. 5 trilayers (2008)
  • Author(s): T. Furubayashi, K. Kodama, H. Sukegawa, Y.K. Takahashi, K. Inomata, K. Hono
  • Journal Title: Appl. Phys. Lett. 93 Pages: 122507
• [Presentation] Current perpendicular to plane giant magnetoresistance of multilayered films using Co2MnSi Heusler alloys (2008)
  • Author(s): K. Kodama, T. Furubayashi, H. Sukegawa, T.M. Nakatani, K. Inomata, K. Hono
  • Organizer: 53rd Annual Conference on Magnetism and Magnetic Materials
  • Place of Presentation: Austin, USA
  • Year and Date: 2008-11-14
• [Presentation] Current-perpendicular-to-plane giant magnetoresistance of a spin valve using Co2MnSi Heusler alloy electrodes (2008)
  • Author(s): T. Furubayashi, K. Kodama, H. Sukegawa, Y.K. Takahashi, K. Inomata, K. Hono
  • Organizer: 53rd Annual Conference on Magnetism and Magnetic Materials
  • Place of Presentation: Austin, USA
  • Year and Date: 2008-11-13
• [Presentation] High spin polarization of Co2MnGa0. 5Sn0. 5 Heusler alloy (2008)
  • Author(s): B. Varaprasad, A. Rajanikanth, Y.K. Takahashi, K. Hono
  • Organizer: 53rd Annual Conference on Magnetism and Magnetic Materials
  • Place of Presentation: Austin, USA
  • Year and Date: 2008-11-13
• [Presentation] Structural characterizations of Co2MnSi/MgO/Co2MnSi tunnel junction
  • Author(s): T.M. Nakatani, Y.K. Takahashi, I. Ishikawa, M. Yamamoto, K. Hono
  • Organizer: 53rd Annual Conference on Magnetism and Magnetic Materials
  • Place of Presentation: Austin, USA.
• [Book] 応用技術の最前線 (2009)
  • Author(s): 高橋有紀子・宝野和博
  • Publisher: シーエムシー出版
• [Patent(Industrial Property Rights)] Co基ホイスラー合金とこれを用いた磁性素子 (2008)
  • Inventor(s): アマナブロルラジャニカンス/高橋有紀子/宝野和博
  • Industrial Property Rights Holder: 物質・材料研究機構
  • Industrial Property Number: 特願2008-299551
  • Filing Date: 2008-11-25
• [Patent(Industrial Property Rights)] Co基ホイスラー合金 (2008)
  • Inventor(s): アマナブロルラジャニカンス/高橋有紀子/宝野和博
  • Industrial Property Rights Holder: 物質・材料研究機構種類:
  • Industrial Property Number: 特願2008-220648
  • Filing Date: 2008-08-29
• [Patent(Industrial Property Rights)] Co基ホイスラー合金 (2008)
  • Inventor(s): バラプラサッド/アマナブロルラジャニカンス/高橋有紀子/宝野和博
  • Industrial Property Rights Holder: 物質・材料研究機構
  • Industrial Property Number: 特願2008-199712
  • Filing Date: 2008-08-01
• [Patent(Industrial Property Rights)] Co基ホイスラー合金 (2007)
  • Inventor(s): 中谷友也/アマナブルラジャニカンス/高橋有紀子/宝野和博
  • Industrial Property Rights Holder: 物質・材料研究機構
  • Industrial Property Number: 特願2007-276353
  • Filing Date: 2007-10-24