Article
Materials Science, Multidisciplinary
Kai Sotthewes, Michiel Nijmeijer, Harold J. W. Zandvliet
Summary: The spatial dependence of the local density of states at the Fermi level on a stepped Au(111) surface was studied, revealing that the periodicity of standing waves is influenced by the exact width of the terraces, leading to a variation between 1.5 and 2.1 nm. This unexpected result is explained by considering the superposition of incident and reflected electron waves, which have a periodicity of lambda(F)/2, and the change in periodicity is attributed to the decaying nature of Friedel oscillations.
Review
Chemistry, Physical
Xuan Song, Teng Zhang, Huixia Yang, Hongyan Ji, Jiatao Sun, Liwei Liu, Yeliang Wang, Hongjun Gao
Summary: This paper reviews the recent progress of TLL electronic features in emerging 2D materials embedded with various 1D nanostructures, including island edges, domain walls, and 1D moire patterns. Novel physical phenomena, such as 1D edge states in 2D transition metal dichalcogenides (TMDs), helical TLL in 2D topological insulators (2DTI), and chiral TLL in 2D quantum Hall systems, are described and discussed at the nanoscale. Challenges and opportunities at the frontier of this research area are also analyzed.
Article
Materials Science, Multidisciplinary
Antonio Esau Del Rio Castillo, M. Laura Soriano, Marek Grzelczak, Mildred Quintana, Maurizio Prato
Summary: A straightforward protocol is proposed to covalently bond gold nanoparticles exclusively at the tips of single-walled carbon nanotubes. The attachment of non-functionalized gold nanoparticles onto the main nanotube body is prevented by the steric hindrance provided by a polymer and surfactant. These novel heterostructures show promising potential for applications in photonics and electronic devices.
Article
Chemistry, Physical
Dawei Kang, Xianghua Kong, Vincent Michaud-Rioux, Ying-Chih Chen, Zetian Mi, Hong Guo
Summary: The study introduces a DFT scheme to quantitatively predict band edge shifts and origins in aqueous 2D photocatalysts, revealing that the band edges are not rigidly shifted and explaining the phenomena through geometric deformation, water dipole, and charge redistribution effects. The upshift of CBM in aqueous MoS2 is found to thermodynamically assist carriers in the hydrogen evolution reaction, supporting its efficiency as a photocatalyst in experiments.
NPJ COMPUTATIONAL MATERIALS
(2021)
Article
Materials Science, Multidisciplinary
A. A. Shanenko, T. T. Saraiva, A. Vagov, A. S. Vasenko, A. Perali
Summary: In this study, we calculate the mean-field and fluctuation-shifted critical temperatures for a two-band superconductor and investigate the sensitivity of thermal fluctuations to the system parameters. We find that the screening mechanism via pair-exchange coupling between bands is relevant for achieving higher critical temperatures in a large class of quasi-one-dimensional multiband superconducting materials.
Article
Materials Science, Multidisciplinary
Nassar Doudin, Kayahan Saritas, Min Li, Inga Ennen, J. Anibal Boscoboinik, Petr Dementyev, Andreas Hutten, Sohrab Ismail-Beigi, Eric I. Altman
Summary: The intrinsic properties of two-dimensional SiO2 were revealed by forming the material on inert Au(111). The formation of a crystalline phase consisting of tetrahedral [SiO4] building units was enabled by SiO deposition. The twisting and rippling of the 2D kagome lattice provide 2D silica with the flexibility to adapt to strain and changes in the crystallographic direction without introducing defects.
ACS MATERIALS LETTERS
(2022)
Article
Chemistry, Inorganic & Nuclear
Guilherme S. L. Fabris, Carlos A. Paskocimas, Julio R. Sambrano, Ricardo Paupitz
Summary: This study proposed and theoretically investigated the physical and chemical properties of non-conventional 2D and tubular structures constructed with combinations of Ga/N atoms. Density Functional Theory was used to determine their mechanical and electronic properties, showing good mechanical stability and characteristics of large band-gap semiconductors.
JOURNAL OF SOLID STATE CHEMISTRY
(2021)
Article
Multidisciplinary Sciences
Hongyuan Li, Shaowei Li, Emma C. Regan, Danqing Wang, Wenyu Zhao, Salman Kahn, Kentaro Yumigeta, Mark Blei, Takashi Taniguchi, Kenji Watanabe, Sefaattin Tongay, Alex Zettl, Michael F. Crommie, Feng Wang
Summary: The Wigner crystal has been a subject of fascination for condensed matter physicists for nearly 90 years and has recently been observed in moire superlattices. This study successfully demonstrates real-space imaging of 2D Wigner crystals in WSe2/WS2 heterostructures using a specially designed non-invasive STM spectroscopy technique.
Article
Nanoscience & Nanotechnology
Erik G. C. P. van Loon, Malte Schueler, Daniel Springer, Giorgio Sangiovanni, Jan M. M. Tomczak, Tim O. O. Wehling
Summary: Two-dimensional materials are influenced by their surroundings, and manipulating the dielectric screening can directly control the insulating state of Mott materials. Many-body calculations show spectroscopic changes and an insulator-to-metal transition through Coulomb engineering. We discuss the experimental conditions for achieving Coulomb engineering of Mott materials based on our proof-of-principle calculations.
NPJ 2D MATERIALS AND APPLICATIONS
(2023)
Article
Chemistry, Multidisciplinary
Daekyu Kim, Sumin Park, Juhyung Choi, Yuanzhe Piao, Lawrence Yoon Suk Lee
Summary: Surface reconstruction plays a crucial role in enhancing the activity of electrocatalysts. This study investigates the surface reconstruction of NiFe2O4 interfaced with NiMoO4 facilitated by Ru doping. It demonstrates that Ru doping can regulate the electronic structure, induce high valence Ni3.6+& delta; species, and promote the formation of highly active Ru-doped NiFeOOH/NiOOH. The optimized electrocatalyst exhibits excellent performance in the oxygen evolution reaction.
Article
Materials Science, Coatings & Films
Florian Brix, Emilie Gaudry
Summary: We have combined density functional theory calculations with an evolutionary algorithm to investigate the possible structural models for two-dimensional Pb films on the Al13Co4(100) quasicrystal surface. Our findings show that the stable structure contains 16 Pb atoms per surface cell, in line with the measured coverage. Alternatively, a metastable structure made of 15 Pb atoms also fits with the experimental observations.
JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A
(2022)
Article
Materials Science, Multidisciplinary
Takahiro Ogino, Insung Seo, Hiroo Tajiri, Masashi Nakatake, Sho-Ichi Takakura, Yudai Sato, Yukio Hasegawa, Yoshihiro Gohda, Kan Nakatsuji, Hiroyuki Hirayama
Summary: Both the root 7 x root 3-In-rect film and the two-monolayer-thick In film on Si substrates showed superconductivity, with a similar Fermi surface contour but slightly different shapes. The interaction between the substrate and the films was found to have a minimal effect on the superconductivity, as the transition temperature T-c remained the same.
Article
Optics
Wei-Min Deng, Ze-Ming Chen, Meng-Yu Li, Chao-Heng Guo, Zhong-Tao Tian, Ke-Xin Sun, Xiao-Dong Chen, Wen-Jie Chen, Jian-Wen Dong
Summary: This study demonstrates the creation of an ideal nodal ring in the visible region using a simple 1D photonic crystal. The pi-Berry phase and drumhead surface states are observed, and by breaking the inversion symmetry, photonic ridge states are formed.
LIGHT-SCIENCE & APPLICATIONS
(2022)
Article
Chemistry, Physical
Hongyuan Li, Shaowei Li, Mit H. Naik, Jingxu Xie, Xinyu Li, Jiayin Wang, Emma Regan, Danqing Wang, Wenyu Zhao, Sihan Zhao, Salman Kahn, Kentaro Yumigeta, Mark Blei, Takashi Taniguchi, Kenji Watanabe, Sefaattin Tongay, Alex Zettl, Steven G. Louie, Feng Wang, Michael F. Crommie
Summary: Scanning tunnelling spectroscopy and ab initio simulations have revealed a strong 3D buckling reconstruction and large in-plane strain redistribution in WSe2/WS2 moire heterostructures, leading to remarkably narrow and highly localized K-point moire flat bands. These findings contradicted previous simplified theoretical models but were in quantitative agreement with ab initio simulations capturing the full 3D structural reconstruction, highlighting the dominance of strain redistribution and 3D buckling in determining the effective moire potential in TMD heterostructures.
Article
Chemistry, Physical
Umamahesh Thupakula, Priya Laha, Gertjan Lippertz, Koen Schouteden, Asteriona-Maria Netsou, Aleksandr Seliverstov, Herman Terryn, Lino M. C. Pereira, Chris Van Haesendonck
Summary: Two-dimensional allotropes of tellurium, known as tellurene, have recently attracted attention in materials research due to their exotic properties in ultrathin form. This study reports the observation of three different 2D superstructures of tellurene on Au(111) surfaces using an alternative experimental deposition approach. The superstructures were characterized using scanning tunneling microscopy and spectroscopy, Auger electron spectroscopy, and field emission AES. The study found that the formation of these superstructures led to changes in the surface reconstruction of Au(111), and the electronic properties of the tellurium atoms showed a strong dependence on their structural arrangement. The emergence of band gaps with a p-type charge character was observed in two of the superstructures on Au(111).
JOURNAL OF CHEMICAL PHYSICS
(2022)
Article
Chemistry, Physical
Dhani Nafday, Christine Richter, Olivier Heckmann, Weimin Wang, Jean-Michel Mariot, Uros Djukic, Ivana Vobornik, Patrick Lefevre, Amina Taleb-Ibrahimi, Julien Rault, Laurent Nicolai, Chin Shen Ong, Patrik Thunstrom, Karol Hricovini, Jan Minar, Igor Di Marco
Summary: In this study, angle-resolved photoemission spectroscopy and density functional theory are used to investigate the electronic structure of self-assembled Bi nanolines on the InAs(100) surface. The results suggest the presence of a flat band associated with the Bi nanolines, indicating a strongly polarized conductivity that makes them suitable for nanowire applications in nanotechnology. The coexistence with an accumulation layer indicates further functionalization potential.
APPLIED SURFACE SCIENCE
(2023)
Article
Chemistry, Multidisciplinary
Zhen Hu, Libo Zhang, Atasi Chakraborty, Gianluca D'Olimpio, Jun Fujii, Anping Ge, Yuanchen Zhou, Changlong Liu, Amit Agarwal, Ivana Vobornik, Daniel Farias, Chia-Nung Kuo, Chin Shan Lue, Antonio Politano, Shao-Wei Wang, Weida Hu, Xiaoshuang Chen, Wei Lu, Lin Wang
Summary: This study reports the observation of the second-order NLHE in type-II Dirac semimetal CoTe2 under time-reversal symmetry. The NLHE is determined by the disorder-induced extrinsic contribution on the broken-inversion-symmetry surface, and terahertz rectification at room temperature is achieved without the need for semiconductor junctions or bias voltage. Remarkable photoresponsivity, response time, and mean noise equivalent power are achieved. This opens a new pathway for low-energy photon harvesting in strongly spin-orbit-coupled and inversion-symmetry-breaking systems.
ADVANCED MATERIALS
(2023)
Article
Chemistry, Physical
I. Palacio, J. Obando-Guevara, L. Chen, M. N. Nair, M. A. Gonzalez Bario, E. Papalazarou, P. Le Fevre, A. Taleb-Ibrahimi, E. G. Michel, A. Mascaraque, A. Tejeda
Summary: The temperature-dependent electronic structure of the light rare-earth antimonide LaSb2 was studied using angle-resolved photoemission (ARPES) measurements and density functional theory (DFT) calculations. The results showed the appearance of band replicas and a folded band at low temperature, indicating the presence of a charge density wave in LaSb2.
APPLIED SURFACE SCIENCE
(2023)
Article
Electrochemistry
Mariano Asteazaran, German Cespedes, Silvina Bengio, Ana Maria Castro Luna
Summary: One of the significant drawbacks of Direct Methanol Fuel Cells is high overpotential for the methanol oxidation reaction, as well as CO poisoning of Pt. In this study, electrocatalysts with suitable properties and outstanding performance have been developed by synthesizing PtCu and PtCuRu materials through a simple and scalable process. The materials were further treated to enhance their surface with a higher density of active sites and surface defects. The trimetallic catalysts showed a substantial reduction in CO electrooxidation and improved methanol oxidation performance.
JOURNAL OF APPLIED ELECTROCHEMISTRY
(2023)
Article
Chemistry, Physical
Antonio J. Martinez-Galera, Haojie Guo, Mariano D. Jimenez-Sanchez, Enrique G. Michel, Jose M. Gomez-Rodriguez
Summary: New opportunities for graphene engineering can be achieved by adjusting interfacial interaction in terms of d-band filling and geometry of the support. Growth of graphene on Rh(110) surfaces shows distinct stripe-like moire patterns and Dirac cones around the Fermi level. The analysis also reveals the existence of two levels of interfacial interaction strength and the presence of Dirac cones in band structures of different rotational domains, indicating potential for novel graphene-metal interfaces.
Article
Chemistry, Physical
Danil W. Boukhvalov, Gianluca D'Olimpio, Federico Mazzola, Chia-Nung Kuo, Sougata Mardanya, Jun Fujii, Grazia Giuseppina Politano, Chin Shan Lue, Amit Agarwal, Ivana Vobornik, Piero Torelli, Antonio Politano
Summary: In recent years, the correlation between topological electronic states in quantum materials and their catalytic activity has attracted attention. However, the physicochemical mechanisms governing catalysis with quantum materials are not fully understood. This study investigates the reactivity and stability of AuSn4, a topological nodal-line semimetal, and reveals that surface oxidation enhances its catalytic activity for the hydrogen evolution reaction. The peculiar atomic structure of oxidized AuSn4 enables the migration of hydrogen atoms through a Sn-O layer with minimal energy barrier, making it a promising catalyst.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2023)
Article
Chemistry, Physical
Federico Mazzola, Yanxue Zhang, Natalia Olszowska, Marcin Rosmus, Gianluca D'Olimpio, Marian Cosmin Istrate, Grazia Giuseppina Politano, Ivana Vobornik, Raman Sankar, Corneliu Ghica, Junfeng Gao, Antonio Politano
Summary: Nonmagnetic chiral crystals are a new type of materials that possess Kramers-Weyl Fermions due to the combination of structural chirality, spin-orbit coupling, and time-reversal symmetry. These materials exhibit unique Fermi surfaces with spin-orbit coupling-induced Chern gaps, leading to exotic transport and optical properties. This study investigates the electronic structure and transport properties of CdAs2, a recently discovered chiral material, using angle-resolved photoelectron spectroscopy and density functional theory. The results suggest that CdAs2 is a promising candidate for novel topological properties and provide valuable insights for the development of spintronic and optical devices based on chiral charges and nontrivial Chern numbers.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2023)
Correction
Physics, Multidisciplinary
Domenico Di Sante, Chiara Bigi, Philipp Eck, Stefan Enzner, Armando Consiglio, Ganesh Pokharel, Pietro Carrara, Pasquale Orgiani, Vincent Polewczyk, Jun Fujii, Phil D. C. King, Ivana Vobornik, Giorgio Rossi, Ilija Zeljkovic, Stephen D. Wilson, Ronny Thomale, Giorgio Sangiovanni, Giancarlo Panaccione, Federico Mazzola
Article
Materials Science, Multidisciplinary
Turgut Yilmaz, Xuance Jiang, Deyu Lu, Polina M. Sheverdyaeva, Andrey V. Matetskiy, Paolo Moras, Federico Mazzola, Ivana Vobornik, Jun Fujii, Kenneth Evans-Lutterodt, Elio Vescovo
Summary: Transition metal dichalcogenides host interesting electronic order states intertwined with non-trivial band topology. Photoemission experiments on 1T-VSe2 reveal a Dirac nodal arc emerging from band inversion, supporting spin-momentum locked topological surface states. The combination of these properties with a non-trivial band topology opens the possibility of additional exotic states.
COMMUNICATIONS MATERIALS
(2023)
Article
Materials Science, Multidisciplinary
J. A. Hofer, S. Bengio, N. Haberkorn
Summary: We investigated the impact of Gd magnetic impurities on the superconducting properties of disordered MoNx thin films grown by reactive co-sputtering at room temperature. The addition of Gd suppressed the superconducting critical temperature and affected the temperature dependence of the upper critical field and the vortex dissipation mechanism. These alterations also impacted the instability of the vortex lattice and limited the maximum achievable vortex velocity during dissipation.
APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING
(2023)
Article
Chemistry, Multidisciplinary
Polina M. Sheverdyaeva, Conor Hogan, Gustav Bihlmayer, Jun Fujii, Ivana Vobornik, Matteo Jugovac, Asish K. Kundu, Sandra Gardonio, Zipporah Rini Benher, Giovanni Di Santo, Sara Gonzalez, Luca Petaccia, Carlo Carbone, Paolo Moras
Summary: Topological insulators are bulk insulators with metallic and fully spin-polarized surface states exhibiting Dirac-like band dispersion. By using spin-resolved photoemission spectroscopy, we show that the topological surface states of a topological insulator interfaced with an antimonene bilayer exhibit nearly full out-of-plane spin polarization within the substrate gap. This phenomenon is connected to a symmetry-protected band crossing of the spin-polarized surface states. The nearly full out-of-plane spin polarization of the topological surface states occurs along a continuous path in the energy-momentum space, and the spin polarization within the gap can be reversibly tuned from nearly full out-of-plane to nearly full in-plane by electron doping. These findings pave the way for advanced spintronics applications that exploit the giant out-of-plane spin polarization of topological surface states.
Article
Materials Science, Multidisciplinary
Atasi Chakraborty, Jun Fujii, Chia-Nung Kuo, Chin Shan Lue, Antonio Politano, Ivana Vobornik, Amit Agarwal
Summary: We present CoTe2 as a type-II Dirac semimetal hosting Lorentz-symmetry violating Dirac fermions near the Fermi energy. Combining ab initio calculations and experimental results, we find a pair of type-II Dirac fermions in CoTe2 above the Fermi energy. In addition, CoTe2 exhibits several topological band inversions and spin-polarized surface states, including out-of-plane spin polarization. This work establishes CoTe2 as a potential candidate for studying Dirac fermiology and applications in spintronic devices, infrared plasmonics, and ultrafast optoelectronics.
Article
Materials Science, Multidisciplinary
M. N. Nair, I. Palacio, A. Mascaraque, E. G. Michel, A. Taleb-Ibrahimi, A. Tejeda, C. Gonzalez, A. Martin-Rodero, J. Ortega, F. Flores
Summary: This study reports an experimental and theoretical investigation of the electron-phonon coupling in α-Sn/Ge(111). The results show the presence of a significant electron-phonon interaction in a specific phase of α-Sn/Ge(111), which may play a role in the formation of different phases at low temperatures.
Article
Materials Science, Multidisciplinary
J. A. Hofer, S. Bengio, S. Suarez, N. Haberkorn
Summary: Tungsten thin films were successfully prepared by reactive sputtering at room temperature using different Ar/N-2 gas mixtures. The study analyzed the role of disorder and chemical composition in the presence of superconductivity. The results showed that nitrogen in the gas mixture caused significant changes in the crystalline structure of the samples. While a small addition of nitrogen stabilized the metastable beta-W phase, increasing nitrogen content led to increased disorder. The study also found that superconductivity may be more closely related to amorphous structures and strained beta-W rather than beta-W stabilized with low nitrogen impurities.
MATERIALS ADVANCES
(2023)
