Quantum transport in disordered topological insulators

• Project/Area Number: 23540376
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Condensed matter physics I
• Research Institution: Sophia University
• Principal Investigator: OHTSUKI Tomi 上智大学, 理工学部, 教授 (50201976)
• Co-Investigator(Renkei-kenkyūsha): SLEVIN Keith 大阪大学, 大学院理学系研究科, 准教授 (90294149) ; IMURA Ken-Ichiro 広島大学, 先端物質科学研究科, 助教 (90391870) ; KAWARABAYASHI Tohru 東邦大学, 理学部, 教授 (90251488)
• Project Period (FY): 2011-04-28 – 2015-03-31
• Project Status: Completed (Fiscal Year 2015)
• Budget Amount: ¥5,590,000 (Direct Cost: ¥4,300,000、Indirect Cost: ¥1,290,000); Fiscal Year 2015: ¥650,000 (Direct Cost: ¥500,000、Indirect Cost: ¥150,000); Fiscal Year 2014: ¥520,000 (Direct Cost: ¥400,000、Indirect Cost: ¥120,000); Fiscal Year 2013: ¥650,000 (Direct Cost: ¥500,000、Indirect Cost: ¥150,000); Fiscal Year 2012: ¥650,000 (Direct Cost: ¥500,000、Indirect Cost: ¥150,000); Fiscal Year 2011: ¥3,120,000 (Direct Cost: ¥2,400,000、Indirect Cost: ¥720,000)
• Keywords: トポロジカル絶縁体 / Dirac半金属 / ワイル半金属 / 状態密度 / スケーリング / 臨界指数 / 相図 / 半金属金属転移 / アンダーソン転移 / スケーリング理論 / 薄膜 / 表面ランダムネス / Dirac電子 / Anderson転移 / ランダムネス / アンダーソン局在 / 量子ホール効果 / 量子スピンホール効果 / 国際研究者交流

Outline of Final Research Achievements

We have studied the disordered topological insulators in two and three dimensions. We first estimated the critical exponents in two dimensional quantum Hall and quantum spin Hall transitions with high accuracy. We then determined the phase diagram of disordered three dimensional topological insulators. In addition, we have analyzed the semi-metal to metal transition of Dirac semi-metals that appear on the phase boundary via the scaling of density of states.

Research Products

• [Journal Article] Engineering Dirac electrons emergent on the surface of a topological insulator (2015)
  • Author(s): Y. Yoshimura, K. Kobayashi, T. Ohtsuki, K.-I. Imura
  • Journal Title: Science and Technology of Advanced Materials Volume: 16 Issue: 1 Pages: 014403-014403
  • DOI: 10.1088/1468-6996/16/1/014403
  • Peer Reviewed / Open Access / Acknowledgement Compliant
• [Journal Article] Near-field optical imaging of light localization in GaN nanocolumn system (2014)
  • Author(s): M. Sakai, Y. Inose, T. Ohtsuki, K. Ema, K. Kishino, T. Saiki
  • Journal Title: Japanese Journal of Applied Physics Volume: 53 Issue: 3 Pages: 030301-030301
  • DOI: 10.7567/jjap.53.030301
  • NAID: 210000143396
  • Peer Reviewed / Acknowledgement Compliant
• [Journal Article] Density of States Scaling at the Semimetal to Metal Transition in Three Dimensional Topological Insulators (2014)
  • Author(s): K. Kobayashi, T. Ohtsuki, K.-I. Imura, I.F. Herbut
  • Journal Title: Physical review letters Volume: 112 Issue: 1 Pages: 016402-016402
  • DOI: 10.1103/physrevlett.112.016402
  • Peer Reviewed / Acknowledgement Compliant
• [Journal Article] Critical exponent for the Anderson transition in the three-dimensional orthogonal universality class (2014)
  • Author(s): K. Slevin, T. Ohtsuki
  • Journal Title: New Journal of Physics Volume: 16 Issue: 1 Pages: 015012-015012
  • DOI: 10.1088/1367-2630/16/1/015012
  • Peer Reviewed / Open Access / Acknowledgement Compliant
• [Journal Article] Disordered Weak and Strong Topological Insulators (2013)
  • Author(s): K. Kobayashi, T. Ohtsuki, K.-I. Imura
  • Journal Title: Physical Review Letters Volume: 110 Issue: 23 Pages: 236803-236803
  • DOI: 10.1103/physrevlett.110.236803
  • Peer Reviewed
• [Journal Article] Experimental proof of universal conductance fluctuation in quasi-one-dimensional epitaxial Bi 2 Se 3 wires (2013)
  • Author(s): Sadashige Matsuo, Kensaku Chida, Daichi Chiba, Teruo Ono, Keith Slevin, Kensuke Kobayashi, Tomi Ohtsuki, Cui-Zu Chang, Ke He, Xu-Cun Ma, Qi-Kun Xue
  • Journal Title: Physical Review B Volume: 88 Issue: 15 Pages: 155438-155438
  • DOI: 10.1103/physrevb.88.155438
  • Peer Reviewed
• [Journal Article] Anomalous Dressing of Dirac Fermions in the Topological Surface State of Bi2Se3, Bi2Te3, and Cu-Doped Bi2Se3 (2013)
  • Author(s): T. Kondo
  • Journal Title: Phys. Rev. Lett Volume: 110 Issue: 6 Pages: 32002-32002
  • DOI: 10.1103/physrevlett.112.068103
  • Peer Reviewed
• [Journal Article] Critical exponent for the quantum spin Hall transition in Z2 network model (2012)
  • Author(s): K. Kobayashi, T. Ohtsuki, K. Slevin
  • Journal Title: International Journal of Modern Physics:Conference Series Volume: 11 Pages: 114-119
  • DOI: 10.1142/s2010194512005995
  • Peer Reviewed
• [Journal Article] Finite Size Scaling of the Chalker-Coddington Model (2012)
  • Author(s): K. Slevin, T. Ohtsuki
  • Journal Title: Intl. J. Mod. Phys. Conf. Series Volume: 11 Pages: 60-69
  • DOI: 10.1142/s2010194512006162
  • Peer Reviewed
• [Journal Article] Finite-size energy gap in weak and strong topological insulators (2012)
  • Author(s): K.-I. Imura, M. Okamoto, Y. Yoshimura, Y. Takane,T. Ohtsuki
  • Journal Title: Phys. Rev. B Volume: 86 Issue: 24
  • DOI: 10.1103/physrevb.86.245436
  • NAID: 120005222693
  • Peer Reviewed
• [Journal Article] Finite Size Scaling of the Chalker-Coddington Model (2012)
  • Author(s): K. Slevin, T. Ohtsuki
  • Journal Title: Proceedings of Localization 2011 (A Satellite Conference of LT 26) Volume: in press Pages: 1-10
  • Peer Reviewed
• [Journal Article] Critical exponent for the quantum spin Hall transition in Z_2 network model (2012)
  • Author(s): K. Kobayashi, T. Ohtsuki, K. Slevin
  • Journal Title: Proceedings of Localization 2011 (A Satellite Conference of LT 26) Volume: in press Pages: 1-5
  • Peer Reviewed
• [Journal Article] Critical exponent for the quantum Hall plateau transition (2011)
  • Author(s): K. Slevin, T. Ohtsuki
  • Journal Title: RIMS Kokyuroku Bessatsu Volume: B27 Pages: 141-147
• [Presentation] Phase diagrams of disordered 3D topological insulators and superconductors (2015)
  • Author(s): T. Ohtsuki
  • Organizer: America Physical Society March Meeting 2015
  • Place of Presentation: San Antonio, USA
  • Year and Date: 2015-03-04
• [Presentation] Finite-size energy gap in weak and strong topological insulators (2013)
  • Author(s): T. Ohtsuki
  • Organizer: Workshop on Disordered and Topological Systems
  • Place of Presentation: Zhejiang University, Hangzhou, China
  • Invited
• [Presentation] Finite Size Scaling of the Chalker-Coddington Model (2011)
  • Author(s): K. Slevin, T. Ohtsuki
  • Organizer: Presented at Localisation 2011(招待講演)
  • Place of Presentation: POSTECH, Korea
• [Presentation] Critical exponent for the quantum spin Hall transition in Z_2 network model (2011)
  • Author(s): K. Kobayashi, T. Ohtsuki, K. Slevin
  • Organizer: Presented at Localisation 2011, POSTECH, Korea
  • Place of Presentation: POSTECH, Korea
• [Presentation] Density of states scaling in disordered 3D topological insulators
  • Author(s): T. Ohtsuki
  • Organizer: Multifractality, Interactions, and Topological Effects Near Anderson Transitions
  • Place of Presentation: Dresden, Germany
  • Invited
• [Book] Conductor-Insulator Quantum Phase Transitions (Chap. 3) (2012)
  • Author(s): K. Slevin, T. Ohtsuki
  • Publisher: Oxford University Press
• [Remarks]
• [Remarks] Tomi Ohtsuki's home page
• [Remarks] Tomi Ohtsuki's homepage
  • URL: http://www.ph.sophia.ac.jp/~tomi/
• [Remarks]
  • URL: http://www.ph.sophia.ac.jp/~tomi/