Article
Chemistry, Multidisciplinary
Qilong Wu, Xiaoshuai Fu, Ke Yang, Hongyu Wu, Li Liu, Li Zhang, Yuan Tian, Long-Jing Yin, Wei-Qing Huang, Wen Zhang, Ping Kwan Johnny Wong, Lijie Zhang, Andrew T. S. Wee, Zhihui Qin
Summary: This study demonstrates a practical approach to producing highly crystalline monolayer MoSe2 using high-temperature-annealed Au foil as a weakly interacting substrate for atmospheric pressure chemical vapor deposition. The low-temperature scanning tunneling microscopy/spectroscopy measurements reveal a honeycomb structure of MoSe2 with a quasi-particle bandgap of 1.96 eV. The weak coupling between the Au(100) surface and MoSe2 is critical for easy transfer of monolayers to another host substrate.
Article
Chemistry, Multidisciplinary
Shijie Sun, Baijin Li, Boyu Fu, Zilin Ruan, Hui Zhang, Wei Xiong, Yong Zhang, Gefei Niu, Jianchen Lu, Xiaoqing Zuo, Lei Gao, Jinming Cai
Summary: Nanoscale low-dimensional chiral architectures have attracted increasing scientific interest due to their potential applications in chiral recognition, separation, and transformation. In this study, large-area two-dimensional chiral networks on Au(111) and one-dimensional metal-liganded chiral chains on Cu(111) were successfully constructed and characterized. The chiral transformation of the chiral networks on Au(111) was analyzed, and the electronic state information was studied using scanning tunneling spectroscopy. The combination of scanning tunneling microscopy and non-contact atomic force microscopy techniques enabled ultra-high-resolution characterization of chiral structures on low-dimensional surfaces.
CHINESE CHEMICAL LETTERS
(2022)
Article
Multidisciplinary Sciences
Lucas Schneider, Philip Beck, Levente Rozsa, Thore Posske, Jens Wiebe, Roland Wiesendanger
Summary: Spin chains proximitized by s-wave superconductors are predicted to enter a mini-gapped phase with topologically protected Majorana modes (MMs) localized at their ends. However, the presence of non-topological end states mimicking MM properties can hinder their unambiguous observation. Here, we report on a direct method to exclude the non-local nature of end states via scanning tunneling spectroscopy by introducing a locally perturbing defect on one of the chain's ends. We apply this method to particular end states observed in antiferromagnetic spin chains within a large minigap, thereby proving their topologically trivial character. A minimal model shows that, while wide trivial minigaps hosting end states are easily achieved in antiferromagnetic spin chains, unrealistically large spin-orbit coupling is required to drive the system into a topologically gapped phase with MMs. The methodology of perturbing candidate topological edge modes in future experiments is a powerful tool to probe their stability against local disorder. Spin chains on superconductors have been studied as a possible venue for zero-energy Majorana bound states at the ends of the chain. Here, the authors observe localized end states in antiferromagnetic chains, but rule out a Majorana origin of these states by perturbing them with local defects.
NATURE COMMUNICATIONS
(2023)
Article
Chemistry, Multidisciplinary
Bo Zhu, Yanwei Wu, Zeyi Zhou, Wenjie Zheng, Yuchen Hu, Yongfei Ji, Lingyao Kong, Rui Zhang
Summary: In this work, large electronic tuning on a WSe2 monolayer is achieved by using different facets of a Au-foil substrate, forming in-plane p-n junctions with remarkable built-in electric fields. This facet-dependent tuning effect is directly visualized by scanning tunneling microscopy and differential conductance spectroscopy. The atomic arrangement of the Au facet effectively changes the interfacial coupling and charge transfer, resulting in different magnitudes of charge doping in WSe2.
Article
Chemistry, Multidisciplinary
Hui Zhang, Jianchen Lu, Xin-Jing Zhao, Baijin Li, Hangjing Zhou, Yong Zhang, Gefei Niu, Boyu Fu, Lei Gao, Yuan-Zhi Tan, Jinming Cai
Summary: This study systematically fabricated anthenes with varying lengths and analyzed their magnetic evolution on the Au(111) surface. The results revealed a transition in magnetic properties associated with the length of the anthenes, showing a weak exchange coupling and charge transfer-induced doublet in longer anthenes.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Multidisciplinary
Hui Zhang, Jianchen Lu, Yong Zhang, Lei Gao, Xin-Jing Zhao, Yuan-Zhi Tan, Jinming Cai
Summary: We demonstrate a synthetic strategy to engineer the magnetism of nanographene by hetero-coupling two precursors on the Au(111) surface. The results show that homo-coupled products have a closed-shell structure, while products with ring defects have an open-shell structure with a total spin number of 1/2. Heterocoupled products on the Au(111) substrate exhibit magnetic structures with total spin quantum numbers of 1/2 and 1 due to carbon skeleton transformations.
CHINESE CHEMICAL LETTERS
(2023)
Article
Materials Science, Multidisciplinary
Gefei Niu, Jianchen Lu, Xingyue Wang, Zilin Ruan, Hui Zhang, Lei Gao, Jinming Cai, Xiao Lin
Summary: By artificially creating a density gradient of selenium concentration, we successfully achieved simultaneous fabrication of two superstructures of CuSe monolayer on a Cu(111) substrate and observed an intermediate state. Scanning tunneling microscopy and spectroscopy measurements showed that the selenium concentration can modulate the superstructure and semiconductor behavior of the CuSe monolayer.
Article
Chemistry, Physical
Jianchen Lu, Shiru Song, Shuai Zhang, Yang Song, Yun Cao, Zhenyu Wang, Li Huang, Hongliang Lu, Yu-Yang Zhang, Sokrates T. Pantelides, Shixuan Du, Xiao Lin, Hong-Jun Gao
Summary: This study reports the fabrication method of a new type of intrinsically patterned 2D material, Ag5Se2, and its selective molecular adsorption behavior. The material exhibits large-scale triangular domains with periodic features, and shows selective adsorption behavior for different molecules.
Article
Chemistry, Multidisciplinary
Daniela Dombrowski, Abdus Samad, Clifford Murray, Marin Petrovic, Pascal Ewen, Thomas Michely, Marko Kralj, Udo Schwingenschlogl, Carsten Busse
Summary: Monolayers of tantalum sulfide were prepared on Au(111) by evaporating Ta in a reactive background of H2S. Different structures were formed under sulfur-rich and sulfur-poor conditions, with TaS identified as a phase derived from 2H-TaS2 by removal of the bottom S layer.
Article
Chemistry, Multidisciplinary
Iris Berg, Luca Schio, Justus Reitz, Elena Molteni, Linoy Lahav, Carolina Gutierrez Bolanos, Andrea Goldoni, Cesare Grazioli, Guido Fratesi, Max M. Hansmann, Luca Floreano, Elad Gross
Summary: In this study, the self-assembly of N-heterocyclic olefins (NHOs) on gold surface was investigated using experimental and computational methods. It was found that NHOs can self-assemble into dimers, trimers, and tetramers, forming stable monolayers. The study also revealed that NHOs can adsorb on gold surface in a flat-lying geometry through coordination with gold adatoms, and the surface interaction can be further increased by functionalizing the backbone with methyl groups, leading to enhanced thermal stability and impact on work-function values.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Physical
Umit Celik, Han Ju Lee, Terell Keel, Logan A. Swartz, Marshall Van Zijll, Cody J. Chalker, T. Randall Lee, Gang-yu Liu
Summary: This study provides molecular-level structural information on dithiol SAMs by investigating OPDT SAMs on Au(111) surfaces, revealing a lack of long-range order in high coverage OPDT SAMs. The study shows that within ordered domains, OPDT molecules can be lying-down or standing-up, randomly distributed on Au(111) with little long-range order.
JOURNAL OF PHYSICAL CHEMISTRY C
(2021)
Article
Chemistry, Multidisciplinary
Meng-Kai Lin, Guan-Hao Chen, Ciao-Lin Ho, Wei-Chen Chueh, Joseph Andrew Hlevyack, Chia-Nung Kuo, Tsu-Yi Fu, Juhn-Jong Lin, Chin Shan Lue, Wen-Hao Chang, Noriaki Takagi, Ryuichi Arafune, Tai-Chang Chiang, Chun-Liang Lin
Summary: Monolayer transition metal dichalcogenides show tunability in electronic properties, with bandgap modulation possible through control of tunneling current. Monolayer PtTe2 exhibits a reversible semiconductor-to-metal transition at moderate tunneling current, attributed to its surface electronic structure coupling with the tunneling tip.
Article
Chemistry, Multidisciplinary
Zhewen Liang, Shiru Wu, Jiamin Wang, Yifan Qin, Fang Cheng, Liang Cao, Hai Xu
Summary: In this study, a method was proposed to construct chiral metal-organic networks on Au(111) surface using PTCDA molecules and low-cost NaCl in a controllable manner. The results showed that the incorporation of Na ions disrupted intermolecular hydrogen bonds and initiated a collective sliding motion of PTCDA molecules. The chirality transfer process was disrupted when intermolecular hydrogen bonds were completely replaced by Na ions. This study provides fundamental insights into the mechanism of coordination-induced chirality and offers potential strategies for synthesizing large homochiral metal-organic networks.
Article
Chemistry, Multidisciplinary
Jingqi Feng, Huiying Gao, Tian Li, Xin Tan, Peng Xu, Menglei Li, Lin He, Donglin Ma
Summary: The interface between metals and semiconductors in two-dimensional electronic heterostructures is crucial for next-generation electronic devices. By phase engineering, lattice-matched heterointerfaces have been achieved in polymorphic 2D transition-metal dichalcogenides MX2, while a single layer of hexagonal Cu2Te crystal has been synthesized through liquid-solid interface growth. The Cu2Te monolayer consists of two lattice-matched distinct phases, resembling the 1T and 1T' phases of MX2, and could potentially lead to nanoscale lattice-matched metal-semiconductor junctions with atomically sharp interfaces.
Article
Chemistry, Multidisciplinary
Qiucheng Li, Xiaolong Liu, Eden B. Aklile, Shaowei Li, Mark C. Hersam
Summary: The study reports the self-assembly of mixed-dimensional lateral heterostructures consisting of 2D metallic borophene and 1D semiconducting armchair-oriented graphene nanoribbons (aGNRs). The systematic study and refinement of on-surface polymerization process from monomers to organometallic intermediates to demetallization result in borophene/aGNR lateral heterojunctions with structurally and electronically abrupt interfaces, providing insight for precise nanoelectronics.
Article
Chemistry, Physical
Masashi Kuwahara, Hideaki Uratsuji, Maho Abe, Hayato Sone, Sumio Hosaka, Joe Sakai, Yoichi Uehara, Rie Endo, Tohru Tsuruoka
APPLIED SURFACE SCIENCE
(2015)
Article
Materials Science, Multidisciplinary
J. U. Ahamed, S. Katano, Y. Uehara
BULLETIN OF MATERIALS SCIENCE
(2015)
Article
Physics, Applied
Yoichi Uehara, Satoshi Katano, Masashi Kuwahara, Tetsu Suzuki
JAPANESE JOURNAL OF APPLIED PHYSICS
(2015)
Article
Chemistry, Physical
Satoshi Katano, Masaki Hotsuki, Yoichi Uehara
JOURNAL OF PHYSICAL CHEMISTRY C
(2016)
Article
Physics, Condensed Matter
Joe Sakai, Masashi Kuwahara, Masaki Hotsuki, Satoshi Katano, Yoichi Uehara
JOURNAL OF PHYSICS-CONDENSED MATTER
(2016)
Article
Metallurgy & Metallurgical Engineering
Jamal Uddin Ahamed, Satoshi Katano, Yoichi Uehara
TRANSACTIONS OF THE INDIAN INSTITUTE OF METALS
(2016)
Article
Physics, Applied
Takeshi Inaoka, Yoich Uehara
JOURNAL OF APPLIED PHYSICS
(2017)
Article
Physics, Applied
Satoshi Katano, Hiroto Fujita, Yoichi Uehara
APPLIED PHYSICS LETTERS
(2018)
Article
Physics, Applied
Yoicihi Uehara, Takeshi Inaoka, Takayuki Nishio, Satoshi Katano
JOURNAL OF APPLIED PHYSICS
(2018)
Article
Physics, Applied
Yoichi Uehara, Junichi Michimata, Shota Watanabe, Satoshi Katano, Takeshi Inaoka
JOURNAL OF APPLIED PHYSICS
(2018)
Article
Chemistry, Physical
Satoshi Katano, Tao Wei, Takumi Sasajima, Ryuhei Kasama, Yoichi Uehara
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2018)
Article
Physics, Applied
Yoichi Uehara
JAPANESE JOURNAL OF APPLIED PHYSICS
(2013)
Article
Physics, Applied
Yoichi Uehara, Masashi Kuwahara, Satoshi Katano, Takenori Tanno, Joe Sakai
JOURNAL OF APPLIED PHYSICS
(2018)
Article
Physics, Condensed Matter
Y. Uehara, M. Kuwahara, S. Katano
SOLID STATE COMMUNICATIONS
(2014)
Article
Metallurgy & Metallurgical Engineering
Jamal Uddin Ahamed, Satoshi Katano, Yoichi Uehara
TRANSACTIONS OF THE INDIAN INSTITUTE OF METALS
(2019)
