NMR study on the inelastic scattering rate governing the spin-lock in the topological insulator

• Project/Area Number: 15K05148
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Condensed matter physics II
• Research Institution: Sophia University
• Principal Investigator: Takayuki GOTO 上智大学, 理工学部, 教授 (90215492)
• Co-Investigator(Kenkyū-buntansha): 田邉 洋一 東北大学, 理学研究科, 助教 (80574649)
• Project Period (FY): 2015-04-01 – 2018-03-31
• Project Status: Completed (Fiscal Year 2017)
• Budget Amount: ¥4,680,000 (Direct Cost: ¥3,600,000、Indirect Cost: ¥1,080,000); Fiscal Year 2017: ¥1,300,000 (Direct Cost: ¥1,000,000、Indirect Cost: ¥300,000); Fiscal Year 2016: ¥1,430,000 (Direct Cost: ¥1,100,000、Indirect Cost: ¥330,000); Fiscal Year 2015: ¥1,950,000 (Direct Cost: ¥1,500,000、Indirect Cost: ¥450,000)
• Keywords: トポロジカル絶縁体 / 薄膜合成 / ＮＭＲ / μＳＲ / 薄膜 / NMR / 表面スピンテキスチャ

Outline of Final Research Achievements

The original purpose of this study is to investigate microscopically the spinlock state within the surface conductive nano-layer of topological insulators. For this purpose, we have developed a method for epitaxial growth of bulk insulating three-dimensional topological insulator (3D-TI) Bi2-xSbxTe3-ySey (BSTS) ultrathin films, ranging from a few quintuple to several hundreds of layers, on mica in a large-area (1 cm2) via catalyst-free physical vapor deposition.

Research Products

• [Journal Article] Thermoelectric properties of 3D topological insulator: Direct observation of topological surface and its gap opened states (2017)
  • Author(s): "Stephane Yu Matsushita, Khuong Kim Huynh, Harukazu Yoshino, Ngoc Han Tu, Yoichi Tanabe, and Katsumi Tanigaki"
  • Journal Title: Physical Revew Materials Volume: 1
  • Peer Reviewed
• [Journal Article] Large-Area and Transferred High-Quality Three-Dimensional Topological Insulator Bi2-xSbxTe3-ySey Ultrathin Film by Catalyst-Free Physical Vapor Deposition (2017)
  • Author(s): Ngoc Han Tu, Yoichi Tanabe, Yosuke Satake, Khuong Kim Huynh, Katsumi Tanigaki
  • Journal Title: Nano letters Volume: 17 Issue: 4 Pages: 2354-2360
  • DOI: 10.1021/acs.nanolett.6b05260
  • Peer Reviewed / Open Access / Int'l Joint Research / Acknowledgement Compliant
• [Journal Article] In-plane topological p-n junction in the three dimensional topological insulator Bi2-xSbxTe3-ySey (2016)
  • Author(s): Ngoc Han Tu, Yoichi Tanabe, Yosuke Satake, Khuong Kim Huynh, Katsumi Tanigaki
  • Journal Title: Nature Communications Volume: 7
  • Peer Reviewed / Open Access / Int'l Joint Research / Acknowledgement Compliant
• [Journal Article] Low-energy μSR Study on the Tetradymite Topological Insulator Bi1.5Sb0.5TeSe (2015)
  • Author(s): Takayuki Goto, Kazuki Matsui, Tadashi Adachi, Tomi Ohtsuki, Ngoc Han Tu, Yoichi Tanabe, Katsumi Tanigaki, Isao Watanabe, Zaher Salman, Andreas Suter, Thomas Prokscha
  • Journal Title: Physics Procedia Volume Volume: 75 Pages: 100-105
  • DOI: 10.1016/j.phpro.2015.12.014
  • Peer Reviewed / Open Access / Int'l Joint Research / Acknowledgement Compliant
• [Presentation] 磁場中輸送特性から見た3次元トポロジカル絶縁体Bi2-xSbxTe3-ySey薄膜の電子状態 (2017)
  • Author(s): 田邉洋一, Tu Ngoc Han, 佐竹遥介, Huynh Kim Khuong, 松下ステファン悠, 谷垣勝巳
  • Organizer: 日本物理学会2016年秋季大会（口頭発表） 2017年9月23日（岩手大学）
• [Presentation] 有機/無機界面での電荷移動を用いて作製した3次元トポロジカル絶縁体p-n接合デバイスの輸送現象 (2016)
  • Author(s): 田邉洋一, Tu Ngoc Han, 佐竹遥介, Huynh Kim Khuong, 谷垣勝巳
  • Organizer: 日本物理学会2016年秋季大会
  • Place of Presentation: 金沢大学（石川県金沢市）
  • Year and Date: 2016-09-15
• [Presentation] Thickness Dependence of Electric Transport in three - dimensional topological insulator Bi1.5Sb0.5Te1.7Se1.3 ultrathin films (2016)
  • Author(s): Ngoc Han Tu, Yoichi Tanabe, Stephane Yu Mastushita, Khuong Kim HuynhB Kastumi Tanigaki
  • Organizer: 日本物理学会2016年秋季大会
  • Place of Presentation: 金沢大学（石川県金沢市）
  • Year and Date: 2016-09-15
• [Presentation] Low-energy μSR study on the tetradymite topological insulator Bi1.5Sb0.5TeSe2 (2016)
  • Author(s): T. Goto, K. Matsui, Tu Ngoc Han, Yoichi Tanabe, Katsumi Tanigaki
  • Organizer: Frontier of the Muon Science Applications RIKEN-RAL Muon Facility 25-Years Operation Cerebration
  • Place of Presentation: 理化学研究所（埼玉県和光市）
  • Year and Date: 2016-02-16
  • Int'l Joint Research
• [Presentation] Low-energy μSR study on the thin-film of tetradymite topological insulator Bi1.5Sb0.5TeSe2 (2016)
  • Author(s): K. Matsui, T. Goto, Tu Ngoc Han, Yoichi Tanabe, Katsumi Tanigaki
  • Organizer: International USMM &CMSI Workshop
  • Place of Presentation: Hongo Campus, The University of Tokyo, Tokyo, Japan
  • Year and Date: 2016-01-05
  • Int'l Joint Research
• [Presentation] Topological p-n junction in three dimentional topological insulator Bi2-xSbxTe3-ySey fabricated by deposition of F4-TCNQ organic molecule (2016)
  • Author(s): Yoichi Tanabe, Ngoc Han Tu, Stephane Yu Mastushita, Khuong Kim HuynhB Kastumi Tanigaki
  • Organizer: The 2nd Conference on Condensed Matter Physics
  • Place of Presentation: Nangjin (China)
• [Presentation] Van deer Waals epitaxial growth of High quality Bi2-xSbxTe3-ySey ultrathin film grown by the catalyst free physical vappor deposition (2016)
  • Author(s): Yoichi Tanabe, Ngoc Han Tu, Stephane Yu Mastushita, Khuong Kim HuynhB Kastumi Tanigaki
  • Organizer: Energy Materials Nanotechnology
  • Place of Presentation: Prague (Czech)
• [Presentation] Large - area synthesis and nondestructive transfer process of high - quality Bi2-xSbxTe3-ySey films (2015)
  • Author(s): Tu Ngoc Han, Yoichi Tanabe, Yosuke Satake, Khuong, Kim Huynh, Katsumi Tanigaki
  • Organizer: 日本物理学会2015年秋季大会
  • Place of Presentation: 関西大学（大阪府吹田市）
  • Year and Date: 2015-09-16
• [Presentation] Low-energy SR study on the tetradymite topological insulator Bi1.5Sb0.5TeSe2 (2015)
  • Author(s): Takayuki Goto, Kazuki Matsui, Tadashi Adachi, Tomi Ohtsuki, Ngoc Han Tu, Yoichi Tanabe, Katsumi Tanigaki, Isao Watanabe, Zaher Salman, Andreas Suter and Thomas Prokscha
  • Organizer: 20th International Conference on Magnetism ICM2015
  • Place of Presentation: Palau de Congress de Catalunya（Barcelona, Spain）
  • Year and Date: 2015-07-05
  • Int'l Joint Research