Development of the electric-field controlled magneto-optical effect

• Project/Area Number: 26709046
• Research Category: Grant-in-Aid for Young Scientists (A)
• Allocation Type: Partial Multi-year Fund
• Research Field: Physical properties of metals/Metal-base materials
• Research Institution: National Institute of Advanced Industrial Science and Technology
• Principal Investigator: NOZAKI TAKAYUKI 国立研究開発法人産業技術総合研究所, スピントロニクス研究センター, 研究チーム長 (60452405)
• Project Period (FY): 2014-04-01 – 2017-03-31
• Project Status: Completed (Fiscal Year 2016)
• Budget Amount: ¥23,530,000 (Direct Cost: ¥18,100,000、Indirect Cost: ¥5,430,000); Fiscal Year 2016: ¥780,000 (Direct Cost: ¥600,000、Indirect Cost: ¥180,000); Fiscal Year 2015: ¥20,670,000 (Direct Cost: ¥15,900,000、Indirect Cost: ¥4,770,000); Fiscal Year 2014: ¥2,080,000 (Direct Cost: ¥1,600,000、Indirect Cost: ¥480,000)
• Keywords: スピントロニクス / 磁気光学効果 / 電圧制御 / 磁性薄膜 / 電界制御 / Spintronics / Magneto-optical effect / Voltage effect / 電圧効果 / 磁気異方性 / Ｓｐｉｎｔｒｏｎｉｃｓ / ｍａｇｎｅｔｏ－ｏｐｔｉｃａｌ ｅｆｆｅｃｔ / ｅｌｅｃｔｒｉｃ－ｆｉｅｌｄ ｅｆｆｅｃｔ

Outline of Final Research Achievements

This project aimed to develop the technique of electric-field control of magneto-optical effect in a ferromagnetic metal layer. We prepared junction structure by the combination of pulse laser deposition for dielectric materials and molecular beam epitaxy or sputtering techniques for metal materials. We found that SrHfO3 can exhibit a relatively high dielectric constant of about 25 with low leak current, which is suitable for voltage-controlled devices. In the device with FeB ferromagnetic layer, we realized the modification of Kerr rotation angle of 0.03 degree, which corresponds to about 60 fJ/Vm as the voltage-induced anisotropy change. We also found that Pt doping at the Fe/MgO interface is effective to enhance the voltage effect as well as the interface magnetic anisotropy. By combining the developed technique, highly-efficient electric-field control of magneto-optical effects can be expected.

Research Products

• [Journal Article] Large Voltage-Induced Changes in the Perpendicular Magnetic Anisotropy of an MgO-Based Tunnel Junction with an Ultrathin Fe Layer (2016)
  • Author(s): T. Nozaki, A. Koziol－Rachwal, W. Skowronski, V. Zayets, Y. Shiota, S. Tamaru, H. Kubota, A. Fukushima, S. Yuasa, Y. Suzuki
  • Journal Title: Phys. Rev. Appl. Volume: ５ Issue: 4
  • DOI: 10.1103/physrevapplied.5.044006
  • Peer Reviewed / Acknowledgement Compliant
• [Journal Article] The effect of the MgO buffer layer thickness on magnetic anisotropy in MgO/Fe/Cr/MgO buffer/MgO(001) (2016)
  • Author(s): A. Koziol-Rachwal, T. Nozaki, V. Zayets, H. Kubota, A. Fukushima, S. Yuasa, Y. Suzuki
  • Journal Title: J. Appl. Phys. Volume: １２０ Issue: 8
  • DOI: 10.1063/1.4961203
  • Peer Reviewed / Acknowledgement Compliant
• [Presentation] Influence of Cr doping on voltage-controlled magnetic anisotropy effect at an ultrathin Fe/MgO interface (2017)
  • Author(s): T. Nozaki, A. Koziol-Rachwal, Y. Shiota, S. Tamaru, H. Kubota, A. Fukushima, Y. Suzuki, S. Yuasa
  • Organizer: 日本応用物理学会
  • Place of Presentation: パシフィコ横浜、横浜市
  • Year and Date: 2017-03-14
• [Presentation] Towards the realization of voltage-torque MRAM ～Prospects and future challenges～ (2016)
  • Author(s): T. Nozaki, Y. Shiota, A. Koziol-Rachwal, W. Skowronski, V. Zayets, S. Tamaru, H. Kubota, A. Fukushima, Y. Suzuki, S. Yuasa
  • Organizer: IEDM2016
  • Place of Presentation: サンフランシスコ、カリフォルニア州、USA
  • Year and Date: 2016-12-05
  • Int'l Joint Research
• [Presentation] Large voltage-controlled magnetic anisotropy change in epitaxial Cr/ultrathin Fe/MgO/Fe magnetic tunnel junctions (2016)
  • Author(s): T. Nozaki, A. Koziol-Rachwal, W. Skowronski, V. Zayets, Y. Shiota, S. Tamaru, H. Kubota, A. Fukushima, Y. Suzuki, S. Yuasa
  • Organizer: 日本磁気学会
  • Place of Presentation: 金沢大学、金沢市
  • Year and Date: 2016-09-05
  • Invited
• [Presentation] Voltage-controlled magnetic anisotropy in an ultrathin Fe layer sandwiched between Cr and MgO layers (2016)
  • Author(s): T. Nozaki, A. Koziol-Rachwal, W. Skowronski, V. Zayets, Y. Shiota, S. Tamaru, H. Kubota, A. Fukushima, Y. Suzuki, S. Yuasa
  • Organizer: ICAUMS2016
  • Place of Presentation: 成功大学、台南、台湾
  • Year and Date: 2016-08-01
  • Int'l Joint Research
• [Presentation] Large voltage-induced anisotropy change in Cr/ultrathin Fe/MgO/Fe magnetic tunnel junctionsⅡ (2016)
  • Author(s): T. Nozaki, A. Koziol-Rachwal, W. Skowronski, K. Yakushiji, Y. Shiota, Z. Zayets, S. Tamaru, H. Kubota, A. Fukushima, Y. Suzuki, and S. Yuasa
  • Organizer: 応用物理学会春季講演会
  • Place of Presentation: 東京都, 東工大大岡山キャンパス
  • Year and Date: 2016-03-22
• [Presentation] Large voltage-induced magnetic anisotropy in epitaxial Cr/ultrathin Fe/MgO/Fe magnetic tunnel junction (2016)
  • Author(s): T. Nozaki, A. Koziol-Rachwal, W. Skowronski, K. Yakushiji, Y. Shiota, Z. Zayets, S. Tamaru, H. Kubota, A. Fukushima, Y. Suzuki, and S. Yuasa
  • Organizer: MMM/INTERMAG 2016 Joint Conference
  • Place of Presentation: SanDiego, USA, Hilton SanDiego
  • Year and Date: 2016-01-14
  • Int'l Joint Research
• [Presentation] Large voltage-induced anisotropy change in Cr/ultrathin Fe/MgO/Fe magnetic tunnel junctions (2015)
  • Author(s): T. Nozaki, A. Koziol-Rachwal, W. Skowronski, K. Yakushiji, Y. Shiota, Z. Zayets, S. Tamaru, H. Kubota, A. Fukushima, Y. Suzuki, and S. Yuasa
  • Organizer: 応用物理学会秋季講演会
  • Place of Presentation: 愛知県, 名古屋国際会議場
  • Year and Date: 2015-09-14
• [Presentation] Voltage-control of magnetic anisotropy ~What's the next target?~ (2015)
  • Author(s): T. Nozaki, A. Koziol-Rachwal, W. Skowronski, K. Yakushiji, Y. Shiota, Z. Zayets, S. Tamaru, H. Kubota, A. Fukushima, Y. Suzuki, and S. Yuasa
  • Organizer: ICMFS2015
  • Place of Presentation: Krakow, Poland, AGH Univ.
  • Year and Date: 2015-07-16
  • Int'l Joint Research / Invited