Spin-polarized surface states and elucidation of the mechanism of appearance of ferromagnetism in 4d transition metal ultrathin films and nano-particles

• Project/Area Number: 25390080
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Thin film/Surface and interfacial physical properties
• Research Institution: Osaka Kyoiku University
• Principal Investigator: KAWAGOE Takeshi 大阪教育大学, 教育学部, 教授 (20346224)
• Project Period (FY): 2013-04-01 – 2016-03-31
• Project Status: Completed (Fiscal Year 2015)
• Budget Amount: ¥5,200,000 (Direct Cost: ¥4,000,000、Indirect Cost: ¥1,200,000); Fiscal Year 2015: ¥1,300,000 (Direct Cost: ¥1,000,000、Indirect Cost: ¥300,000); Fiscal Year 2014: ¥1,300,000 (Direct Cost: ¥1,000,000、Indirect Cost: ¥300,000); Fiscal Year 2013: ¥2,600,000 (Direct Cost: ¥2,000,000、Indirect Cost: ¥600,000)
• Keywords: 走査型トンネル顕微鏡 / Pd薄膜 / 強磁性発現機構 / 表面準位 / Pd(001)薄膜 / 表面ナノ構造 / 局所状態密度 / エピタキシャル成長 / STS

Outline of Final Research Achievements

In this research, we studied surface nanostructure, local density of states, and magnetism of ultrathin Pd films by scanning tunneling microscope/spectroscopy (STM/STS), low energy low-energy electron diffraction (LEED) to verify experimentally the origin of the appearance of ferromagnetism in ultrathin Pd films.
High quality epitaxial Pd(001) films, consisting of atomically flat terraces, were successfully grown by using the UHV system equipped with MBE and STM. The dI/dV spectra of the 4ML thick of Pd(001) film shows a distinct peak at +250 mV, which may correspond to the spin-polarized surface states of Pd(001) surface. We have studied the Pd thickness dependence of lattice constants by the LEED patterns, and they turns out that the Pd(001) films show lattice expiations.

Research Products

• [Journal Article] Spin reorientation and large magnetic anisotropy of metastable bcc Co islands on Au(001) (2014)
  • Author(s): T. Miyamachi, T. Kawagoe, S. Imada, M. Tsunekawa, H. Fujiwara, M. Geshi, A. Sekiyama, K. Fukumoto, F. H. Chang, H. J. Lin, F. Kronast, H. Durr, C. T. Chen, and S. Suga
  • Journal Title: Physical Review B Volume: 90 Issue: 17
  • DOI: 10.1103/physrevb.90.174410
  • Peer Reviewed
• [Presentation] Au(001)上Cr(001)超薄膜の表面磁性と構造-スピンSTMによる観察 (2016)
  • Author(s): 川越 毅、岡 亮成
  • Organizer: 日本物理学会第71回年次大会
  • Place of Presentation: 東北大学泉キャンパス
  • Year and Date: 2016-03-19
• [Presentation] Surface nanostructure and magnetism of ultrathin Pd(001) films on Au(001) (2015)
  • Author(s): T. Kawagoe, N. Kutsuzawa, and K. Kondoh
  • Organizer: The 20th International Conference on Magnetism
  • Place of Presentation: Barcelona, Spain
  • Year and Date: 2015-07-05
  • Int'l Joint Research
• [Presentation] Au(001)上Pd(001)薄膜の表面ナノ構造と磁性 (2014)
  • Author(s): 川越 毅、沓澤直人、近藤賢治
  • Organizer: 日本物理学会2014年秋季大会
  • Place of Presentation: 中部大学
  • Year and Date: 2014-09-07 – 2014-09-10
• [Presentation] STM/STS study of ultrathin Pd(001) films on Au(001) (2014)
  • Author(s): T. Kawagoe, Y. Yoshimoto, M. Kamoto, N. Kondoh, and N. Kutsuzawa
  • Organizer: SP-STM5 ; Spin-Polarized Scanning Tunneling Microscopy Coference
  • Place of Presentation: Sawmill Creek Resort, Huron, Ohio USA
  • Year and Date: 2014-07-15 – 2014-07-19
• [Presentation] Au(001)上Pd(001)超薄膜のSTM/STS観察 (2013)
  • Author(s): 川越 毅、芳本 祐樹、嘉本 未奈
  • Organizer: 日本物理学会 2013年秋季大会
  • Place of Presentation: 徳島大学常三島キャンパス