Research Topic

Charge and Spin Transport at Molecular Structures Studied by Functional Four-Tip STM

Research Aim

The purpose of this research is to use the functional multi-probe scanning tunneling microscope (STM) that we developed to measure the electron and spin transport properties of two- and three-dimensional components, such as the various molecular structures and electrode surface structures necessary to molecular architectonics created by other groups working on this research area. This will allow us to elucidate their functional properties, and reflect them in the molecular architectural design.

Role and Need in the Group

Our research will focus on wire-like molecular structures, such as those of the macromolecular oligothiophene wire that the Tada Group plans to research, as a sample of 4-probe STM measurement of a molecular structure synthesized in this research area. In addition to the electrical properties, we will also focus on measuring the spin transport characteristics using a magnet-coated CNT probe. Because a theoretical grounding is necessary to analyze the data we obtain, we will proceed with the data analysis in cooperation with the A03-1 Asai Group and A02-2 Ishida Group.

Research Content

1. Replace the SEM controller of the 4-probe STM with a unique controller and aim for a high-resolution, low-current operation mode of the SEM to enable the observation of molecular structures. 2. Simplify the fabrication process for CNT probes and stabilize their quality. We will focus on establishing a probe fabrication process that achieves good reproducibility of the magnetization state of the magnet-coated CNT probe. 3. Using the above technology and an existing ultra-high vacuum (UHV) 4-probe STM device, we will measure the electron and spin transport properties of the molecular structure and electrode substrate surface to be observed in this research, and reflect the results in the molecular architecture. We will perform microfabrication of the electrode substrate surface with an ultra-high vacuum focused ion beam (FIB) that is built into the device, which will be useful for measuring the conductive properties of the structure of individual molecules.a03-2.jpg



Research representative: Shuji Hasegawa /
Member of the research project: Toru Hirahara Assistant Professor / University of Tokyo Graduate School of Science

Papers List


[27] Observation of Anisotropic Band Splitting in Monolayer NbSe2: Implications for Superconductivity and Charge Density Wave

Y. Nakata; K. Sugawara; S. Ichinokura; Y. Okada; T. Hitosugi; T. Koretsune; S. Hasegawa; T. Sato; T. Takahashi
npj 2D Materials and Applications, 2, 12-1 - 12-6, 2018/5/3
DOI: 10.1038/s41699-018-0057-3

[26] Comment on ``Quantum transport in the surface states of epitaxial Bi(111) thin films''

T. Hirahara; S. Hasegawa


[25] 2層グラフェン層間化合物の2次元超伝導

高橋隆; 菅原克明; 一ノ倉聖; 高山あかり; 長谷川修司
表面科学, 38, 9, 460 - 465, 2017/9/20
DOI: 10.1380/jsssj.38.460

[24] Emergence of charge density waves and a pseudogap in single-layer TiTe2

P. Chen; Woei Wu Pai; Y.-H. Chan; A. Takayama; C.-Z. Xu; A. Karn; S. Hasegawa; M. Y. Chou; S.-K. Mo; A.-V. Fedorov; T.-C. Chiang
Nature Communications , 8, 516-1 - 516-6, 2017/9/11
DOI: 10.1038/s41467-017-00641-1

[23] Large-gap magnetic topological heterostructure formed by subsurface incorporation of a ferromagnetic layer

T. Hirahara; S. V. Eremeev; T. Shirasawa; Y. Okuyama; T. Kubo; R. Nakanishi; R. Akiyama; A. Takayama; T. Hajiri; S. Ideta; M. Matsunami; K. Sumida; K. Miyamoto; Y. Takagi; K. Tanaka; T. Okuda; T.Yokoyama; S. Hasegawa
Nano Letters, 17, 3493 - 3500, 2017/5/26
DOI: 10.1021/acs.nanolett.7b00560

[22] Berry phase shift from 2π to π in Bilayer graphene by Li-intercalation and sequential desorption

R. Akiyama; Y. Takano; Y. Endo; S. Ichinokura; R. Nakanishi; K. Nomura; S. Hasegawa
Applied Physics Letters, 110, 23, 233106-1 - 233106-4, 2017/6/6
DOI: 10.1063/1.4984958

[21] Superconductivity in thallium double atomic layer and transition into an insulating phase intermediated by a quantum metal state

S. Ichinokura; L. Bondarenko; A. Tupchaya; D. Gruznev; A. Zotov; A. Saranin; S. Hasegawa
2D Materials, 4, 025020-1 - 025020-10, 2017/2/1
DOI: 10.1088/2053-1583/aa57f9


[20] Superconducting Calcium-Intercalated Bilayer Graphene [重要文献]

S. Ichinokura; K. Sugawara; A. Takayama; T. Takahashi; S. Hasegawa
ACS Nano, 10, 2, 2761 - 2765, 2016/1/27
DOI: 10.1021/acsnano.5b07848

[19] Development of a convenient in situ UHV scanning tunneling potentiometry

T. Nakamura; R. Yoshino; R. Hobara; S. Hasegawa; T. Hirahara
e-Journal of Surface Science and Nanotechnology, 14, 216 - 224, 2016/11/12
DOI: 10.1380/ejssnt.2016.216

[18] In situ 電気伝導測定によるRashba 型表面構造(Tl, Pb)/Si(111)の超伝導の観測

一ノ倉聖; 保原麗; 高山あかり; 長谷川修司; Andrey V. MATETSKIY; Leonid V. BONDARENKO; Alexandra Y. TUPCHAYA; Dimitry V. GRUZNEV; Andrey V. ZOTOV; Alexander A. SARANIN
表面科学, 37, 8, 363 - 368, 2016/8/10


[17] Role of Quantum and Surface-State Effects in the Bulk Fermi Level Position of Ultrathin Bi films

T. Hirahara; T. Shirai; T. Hajiri; M. Matsunami; K. Tanaka; S. Kimura; S. Hasegawa; K. Kobayashi
Physical Review Letters, 115, 10, 106803-1 - 106803-5, 2015/9/4
DOI: 10.1103/PhysRevLett.115.106803

[16] Two-dimensional superconductor with giant Rashba effect: One-atomic-layer Tl-Pb compound on Si(111)

A.V. Matetskiy; S. Ichinokura; L.V. Bondarenko; A.Y. Tupchaya; D.V. Gruznev; A.V. Zotov; A.A. Saranin; R. Hobara; A. Takayama; S. Hasegawa
Physical Review Letters, 115, 14, 147003-1 - 147003-5, 2015/10/2
DOI: 10.1103/PhysRevLett.115.147003

[15] Direct observation of a gap opening in topological interface states of MnSe/Bi2Se3 heterostructure

A. V. Matetskiy; I. A. Kibirev; T. Hirahara; S. Hasegawa; A. V. Zotov; A. A. Sarani
Applied Physics Letters, 107, 9, 091604-1 - 091604-4, 2015/9/10
DOI: 10.1063/1.4930151

[14] ビスマス表面におけるスピン依存イオン散乱

一ノ倉聖; 平原徹; 酒井治; 長谷川修司; 鈴木拓
表面科学, 36, 8, 408 - 411, 2015/8/10
DOI: 10.1380/jsssj.36.408

[13] 表面での電子・スピン輸送研究の最近の展開

表面科学, 36, 112 - 117, 2015


[12] Electron-spin dependent 4He+ ion scattering on Bi surfaces

*S. Ichinokura; T. Hirahara; S. Hasegawa; O. Sakai; T.T. Suzuki
Radiation Effects and Defects in Solids , 169, 1003 - 1009, 2014

[11] In-situ Micro-fabrication and Measurements of Bi2Se3 Ultrathin Films in a Multi-chamber System having Focus Ion Beam, Molecular Beam Epitaxy, and Four-Tip Scanning Tunneling Microscope

*N. Fukui; R. Hobara; T. Hirahara; Y. Miyatake; H. Mizuno; T. Sasaki; T. Nagamura; S. Hasegawa
e-Journal of Surface Science and Nanotechnology, 12, 423 - 430, 2014

[10] Structure and transport properties of Cu doped Bi2Se3 films

*T. Shirasawa; M. Sugiki; T. Hirahara; M. Aitani; T. Shirai; S. Hasegawa; T. Takahashi
Physical Review B, 89, 195311-1 - 195311-6, 2014

[9] Anisotropic Electronic Conduction in Metal Nanofilms Grown on a One-Dimensional Surface Superstructure

*N. Nagamura; R. Hobara; T. Uetake; T. Hirahara; M. Ogawa; T. Okuda; K. He; P. Moras; P. M. Sheverdyaeva; C. Carbone; K. Kobayashi; I. Matsuda; S. Hasegawa
Physical Review B, 89, 125415-1 - 125415-5, 2014

[8] In-situ Micro-fabrication and Measurements of Bi2Se3 Ultrathin Films in a Multi-chamber System having Focus Ion Beam, Molecular Beam Epitaxy, and Four-Tip Scanning Tunneling Microscope

N. Fukui; R. Hobara; T. Hirahara; Y. Miyatake; H. Mizuno; T. Sasaki; T. Nagamura; S. Hasegawa
e-Journal of Surface Science and Nanotechnology, 12, 423 - 430, 2014/10/11
DOI: 10.1380/ejssnt.2014.423

[7] In situ Magnetotransport Measurements of Ultrathin Bi films: Evidence for a Surface-Bulk Coherent Transport

M. Aitani; T. Hirahara; S. Ichinokura; M. Hanaduka; D. Y. Shin; S. Hasegawa
Physical Review Letters, 113, 20, 206802-1 - 206802-5, 2014/11/14
DOI: 10.1103/PhysRevLett.113.206802

[6] Redox Control and High Conductivity of Nickel Bis(dithiolene) Complex π-Nanosheet: A Potential Organic Two-Dimensional Topological Insulator

Tetsuya Kambe; Ryota Sakamoto; Tetsuro Kusamoto ; Tigmansu Pal ; Naoya Fukui; Ken Hoshiko ; Takahiro Shimojima ; Zhengfei Wang ; Toru Hirahara ; Kyoko Ishizaka ; Shuji Hasegawa ; Feng Liu; Hiroshi Nishihara
Journal of the American Chemical Society, 136, 41, 14357 - 14360, 2014/9/24
DOI: 10.1021/ja507619d

[5] Structure Determination of Multilayer Silicene Grown on Ag(111) films by Electron Diffraction: Evidence for Ag Segregation at the Surface

Terufusa Shirai; Tetsuroh Shirasawa; Toru Hirahara; Naoya Fukui; Toshio Takahashi; Shuji Hasegawa
PHYSICAL REVIEW B, 89, 24, 241403-1 - 241403-5, 2014/6/10
DOI: 10.1103/PhysRevB.89.241403


[4] Fermi level tuning of topological insulator thin films

M. Aitani; Y. Sakamoto; *T. Hirahara; M. Yamada; H. Miyazaki; M. Matsunami; S. Kimura; S. Hasegawa
Japanese Journal of Applied Physics , 52, 110112-1 - 110112-8, 2013

[3] In situ transport measurements on ultrathin Bi(111) films using a magnetic tip: Possible detection of current-induced spin polarization in the surface states

T. Tono; *T. Hirahara; S. Hasegawa
New Journal of Physics , 15, 105018-1 - 105018-14, 2013

[2] Evidence of Dirac Fermions in Multilayer Silicene

*P. De Padova; P. Vogt; A. Resta; J. Avila; I. Razado-Colambo; C. Quaresima; C. Ottaviani; B. Olivieri; T. Bruhn; T. Hirahara; T. Shirai; S. Hasegawa; M. C. Asensio; G. Le Lay
Applied Physics Letters, 102, 163106-1 - 163106-3, 2013

[1] Magnetotransport measurements of a superconducting surface state of In- and Pb-induced structures on Si(111)

M. Yamada; *T. Hirahara; S. Hasegawa
Physical Review Letters , 110, 237001-1 - 237001-5 , 2013