Article
Physics, Multidisciplinary
Xin Chen, Linyang Li, Francois M. Peeters, Biplab Sanyal
Summary: The oxidized dumbbell silicene structures exhibit semimetallic properties with Dirac cones at the Fermi level, making them potential candidates for applications in quantum computing and high-speed electronic devices. The excellent properties of oxidized dumbbell silicene are sensitive to compression due to the self-absorption effect, but remain robust against tensile strain.
NEW JOURNAL OF PHYSICS
(2021)
Article
Chemistry, Physical
Akihiro Nagoya, Ritsuko Yaokawa, Nobuko Ohba
Summary: In this study, the effect of fluorine diffusion on the phase transformation of silicene in calcium disilicide was investigated. The results showed fluorine aggregation at low concentrations and predicted a transformation from MLSi to BLSi. The observations were confirmed by both experimental and computational analyses, indicating a destabilization of MLSi structure and transformation to BLSi due to the aggregated fluorine atoms.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2021)
Article
Materials Science, Multidisciplinary
Honghua Ma, Meijun Liu, Li Wen, Qianguang Li, Huan Chen, Xunong Yi
Summary: This study investigates the Goos-Hanchen shift of silicene in different phases and finds a large negative spatial GH shift in metal phases and a positive shift in nonmetallic states. The angular GH shift varies rapidly near the pseudo-Brewster angle, allowing manipulation of the GH effect by controlling external circularly polarized light electric field or magnetic field. These results are believed to be helpful for developing novel optoelectronic devices based on the GH effect of silicene.
RESULTS IN PHYSICS
(2021)
Article
Materials Science, Multidisciplinary
Sabreen S. Hammouda, Thomas Mueller, Eugen Weschke, Manuel Angst
Summary: A comprehensive investigation of the magnetic properties of intercalated Lu2Fe3O7 was carried out using dc magnetization, polarized neutron scattering, and x-ray magnetic circular dichroism (XMCD) measurements. The results showed a spin order in each Fe-O bilayer similar to that in the nonintercalated LuFe2O4, with a paramagnetic-like magnetic moment induced in the Fe-O single layers by an applied magnetic field. Additionally, spin-charge coupling was revealed through XMCD measurements.
Article
Chemistry, Physical
Filippo Fabbri, Manuela Scarselli, Naveen Shetty, Sergey Kubatkin, Samuel Lara-Avila, Mathieu Abel, Isabelle Berbezier, Holger Vach, Matteo Salvato, Maurizio De Crescenzi, Paola Castrucci
Summary: Epitaxial graphene has been proven to be an excellent substrate for synthesizing two-dimensional materials. Silicene, a highly anticipated material, has been successfully grown on a slightly defective epitaxial graphene network, opening possibilities for controlled intercalation of silicon atoms and future nanotechnology applications.
SURFACES AND INTERFACES
(2022)
Article
Physics, Applied
Emeric Deylgat, Sabyasachi Tiwari, William G. Vandenberghe, Bart Soree
Summary: Topological insulators have unique properties that make them promising for next-generation electronic devices. Passivating stanene nanoribbons is necessary for their implementation in devices. We develop a tight-binding model based on the Kane-Mele model and show its agreement with density functional theory calculations, capturing the physics of passivated edge bands.
JOURNAL OF APPLIED PHYSICS
(2022)
Article
Materials Science, Multidisciplinary
Tie Yang, Chengwu Xie, Hong Chen, Xiaotian Wang, Gang Zhang
Summary: In this work, an authentic material, Ta3Sn, with phononic nodal points featuring both quadratic dispersion and maximum band degeneracy is proposed based on first-principles calculations. The corresponding symmetry analysis deepens the understanding of the relative physics. Evident arc-shaped surface states, originating from the projected phononic nodal points, can strongly benefit the experimental detection.
Article
Chemistry, Multidisciplinary
Tsukasa Terada, Yuto Uematsu, Takafumi Ishibe, Nobuyasu Naruse, Kazunori Sato, Tien Quang Nguyen, Eiichi Kobayashi, Hideyuki Nakano, Yoshiaki Nakamura
Summary: This study proposes a method to deform the buckled structure in layered silicene by controlling the intercalated atoms, which can significantly enhance its thermoelectric properties. The results experimentally demonstrate that by deforming the silicene buckled structure, the power factor can be greatly enhanced compared to conventional materials.
ADVANCED MATERIALS INTERFACES
(2022)
Article
Crystallography
Mustahseen M. Indaleeb, Sourav Banerjee
Summary: The article investigates the phenomenon of Dual-Dirac-like cones (DDC) occurring simultaneously at the center of the Brillouin zone and how to achieve this phenomenon through tuning parameters. Results show that the antisymmetric deaf bands at different energy levels play a crucial role in tracking the DDC. By rotating the PnCs mechanism, frequencies are successfully tracked to form the DDC.
Article
Materials Science, Multidisciplinary
Kang Wang
Summary: The study investigates the transmission of narrow electromagnetic beams in a graphenelike triangular metallic photonic crystal. The metallic structure, local resonance modes, and coupling with incident field all play crucial roles in determining the propagation of the beams. Understanding these interactions at elementary structure scales could find applications in valley photonics for transport tuning and optimization.
Article
Chemistry, Multidisciplinary
Oleg E. Parfenov, Alexander N. Taldenkov, Dmitry V. Averyanov, Ivan S. Sokolov, Oleg A. Kondratev, Mikhail M. Borisov, Sergey N. Yakunin, Igor A. Karateev, Andrey M. Tokmachev, Vyacheslav G. Storchak
Summary: Silicene, a Si-based analogue of graphene, has exceptional properties but high chemical reactivity, making it challenging to work with. This study demonstrates that the number of monolayers in the compound SrSi2 controls the electronic state. By synthesizing films of different thicknesses and using various characterization techniques, the researchers reveal the evolution of the electronic behavior from bulk to ultrathin films.
MATERIALS HORIZONS
(2022)
Article
Nanoscience & Nanotechnology
B. Mortazavi, F. Shojaei, X. Zhuang
Summary: The study revealed that beryllium polynitride (BeN4) and magnesium polynitride (MgN4) monolayers exhibit anisotropic Dirac cones in their electronic structure, while platinum polynitride (PtN4) monolayer is predicted to be a narrow bandgap semiconductor, and iridium polynitride (IrN4) and rhodium polynitride (RhN4) monolayers are metallic systems.
MATERIALS TODAY NANO
(2021)
Review
Physics, Multidisciplinary
Jie Luo, Yun Lai
Summary: Accidental degeneracy plays a vital role in the generation of novel band dispersions. Structures exhibiting accidental Dirac-like conical dispersion at the center of the Brillouin zone can have unique features, such as zero-index behavior and wave tunneling. Introduction of non-Hermiticity in the system can lead to appearance of exceptional points and various other unique dispersions. Similar phenomena are observed in phononic structures.
FRONTIERS IN PHYSICS
(2022)
Article
Materials Science, Multidisciplinary
O. Oubram, J. G. Rojas-Briseno, S. Molina-Valdovinos, I Rodriguez-Vargas
Summary: Contrary to expectations, this study finds that structural disorder can improve the magnetoresistive and spin-valleytronic properties of magnetic silicene superlattices. The results show that structural disorder eliminates conductance oscillations and differentiates the conductance response for parallel and antiparallel magnetization configuration, thus enhancing the magnetoresistance response and spin-valley polarization. Magnetic silicene superlattices with moderate structural disorder are more convenient for designing versatile devices with magnetoresistive and spin-valleytronic capabilities.
Article
Chemistry, Inorganic & Nuclear
Yujie Song, Haoyu Niu, Zhuo Zeng, Dequan Jiang, Xiong He, Youyuan Liang, Hao Huang, Mengsi Zhang, Jinyang Li, Zhangzhen He, Lixia Xiao, Zhengcai Xia
Summary: A novel transition metal tellurate single-crystal BaNi2TeO6 with layered honeycomb lattices has been successfully synthesized. The crystal structure reveals the presence of Ni2+ honeycomb lattice layers and Te6+ triangle lattice layers. BaNi2TeO6 exhibits an antiferromagnetic transition at around 25K and field-induced magnetic transitions at 16.2T and 42.2T, indicating a complex spin structure. The magnetic properties of BaNi2TeO6 are significantly influenced by intercalated ions, Ba2+, compared to the isostructural Na2Ni2TeO6.
INORGANIC CHEMISTRY
(2022)
Article
Physics, Multidisciplinary
Anh D. Phan, Alessio Zaccone, Vu D. Lam, Katsunori Wakabayashi
Summary: The theoretical study predicts compression-induced rejuvenation and strain hardening in metallic glasses, mainly controlled by local cage dynamics. External pressure restricts dynamical constraints and slows down atomic mobility, inducing a rejuvenated metastable state at a higher energy. Consequently, compressed metallic glasses can rejuvenate and exhibit reversible relaxation, leading to strain hardening in mechanical deformation experiments. The theoretical predictions are in good agreement with experimental observations.
PHYSICAL REVIEW LETTERS
(2021)
Article
Multidisciplinary Sciences
Soumya Ranjan Das, Katsunori Wakabayashi, Kazuhito Tsukagoshi, Sudipta Dutta
SCIENTIFIC REPORTS
(2020)
Article
Optics
Huyen Thanh Phan, Feng Liu, Katsunori Wakabayashi
Summary: In this study, we investigate the topological states of honeycomb photonic crystals without inversion symmetry using plane wave expansion and finite element methods. Our findings show that topological corner states appear at 60 degree corners, but are absent at other corners, suggesting a sign flip of valley Chern number at the corner. This research provides an experimentally feasible platform for exploring valley-dependent higher-order topology in photonic systems.
Article
Nanoscience & Nanotechnology
Itsuki Yonemori, Sudipta Dutta, Kosuke Nagashio, Katsunori Wakabayashi
Summary: This study investigates the electronic and phononic properties of thin films of tin sulfide using first-principles calculations, identifying the characteristic Raman active phonon modes and their dependence on the number of layers and stacking sequences. The research also clarifies the relationship between stacking structures and Raman active modes for bilayer tin sulfide.
Article
Nanoscience & Nanotechnology
Mihiro Takeuchi, Yukiya Umeta, Hiroshi Suga, Takatsugu Wakahara, Ying-Chiao Wang, Yasuhisa Naitoh, Katsunori Wakabayashi, Kazuhito Tsukagoshi
Summary: Fullerene derivatives can improve the transport properties of devices through chemical functionalization, and the polymerization and depolymerization of fullerene polymer strings can be controlled to achieve resistance switching elements.
ACS APPLIED NANO MATERIALS
(2022)
Article
Multidisciplinary Sciences
Vladimir S. Prudkovskiy, Yiran Hu, Kaimin Zhang, Yue Hu, Peixuan Ji, Grant Nunn, Jian Zhao, Chenqian Shi, Antonio Tejeda, David Wander, Alessandro De Cecco, Clemens B. Winkelmann, Yuxuan Jiang, Tianhao Zhao, Katsunori Wakabayashi, Zhigang Jiang, Lei Ma, Claire Berger, Walt A. de Heer
Summary: This study demonstrates that annealed edges in conventionally patterned graphene grown on a silicon carbide substrate are stabilized and support a protected edge state. The edge state has a long mean free path and involves a non-degenerate zero-energy quasiparticle.
NATURE COMMUNICATIONS
(2022)
Article
Engineering, Electrical & Electronic
Masato Takei, Mihiro Takeuchi, Hiroshi Suga, Takatsugu Wakahara, Katsunori Wakabayashi, Susumu Okada, Kazuhito Tsukagoshi
Summary: Electromechanical switching was achieved in fullerene C-60 nanochains using a C-60 pyrrolidine tris-acid(CPTA) film in nanogap electrodes. A conductive C(60) chain formed spontaneously in the nanogap without electron beam irradiation. The switching operation from a high-resistance state to a low-resistance state was reproducible and could be executed at room temperature.
ACS APPLIED ELECTRONIC MATERIALS
(2023)
Article
Materials Science, Multidisciplinary
Ren Habara, Katsunori Wakabayashi
Summary: In this study, the nonlinear optical and spin conductivities of NbSe2 are numerically calculated using an effective tight-binding model, considering different optical effects such as symmetry manipulation and bulk photovoltaic effect. The results demonstrate that by controlling the polarization of light, current can be generated and its direction can be altered. This finding is significant for the design of opto-spintronic devices based on 2D materials.
Article
Materials Science, Multidisciplinary
Keisuke Nakagahara, Katsunori Wakabayashi
Summary: This paper numerically calculates the optical conductivity of Graphene on h-BN (G/hBN) under circularly polarized light irradiation. It is found that the lack of spatial inversion symmetry in G/hBN induces valley polarization, which becomes most pronounced in the infrared and terahertz regions if the twist angle between two materials is close to zero for the nondoping case. However, the valley polarization is insensitive to the twist angle for the hole-doped case. These findings provide valuable insights for designing valleytronics devices using G/hBN.
Article
Physics, Multidisciplinary
Ren Habara, Katsunori Wakabayashi
Summary: In this paper, we numerically calculate the nonlinear optical Hall conductivity and selection rules in NbSe2, a metallic two-dimensional transition-metal dichalcogenide material. We show that odd-number-layered NbSe2 exhibits a nonvanishing nonlinear optical Hall conductivity for second harmonic generation, while even-number-layered NbSe2 can generate nonlinear optical Hall currents by breaking inversion symmetry with applied electric fields. These findings have implications for the design of opt-spintronics devices based on 2D materials.
PHYSICAL REVIEW RESEARCH
(2022)
Article
Materials Science, Multidisciplinary
Keiju Sato, Naoki Hayashi, Takahiro Ito, Noriyuki Masago, Makoto Takamura, Mitsuru Morimoto, Takuji Maekawa, Doyoon Lee, Kuan Qiao, Jeehwan Kim, Keisuke Nakagahara, Katsunori Wakabayashi, Hiroki Hibino, Wataru Norimatsu
Summary: Researchers fabricated twisted bilayer graphene samples with an area exceeding 3 x 5 mm(2) and observed a flat band and large bandgap using angle-resolved photoemission spectroscopy, indicating the presence of superconductivity.
COMMUNICATIONS MATERIALS
(2021)
Article
Physics, Multidisciplinary
Feng Liu, Katsunori Wakabayashi
Summary: Higher-order topological corner states can appear in monolayer graphene without introducing additional effects; the emergence of corner states depends on the corner angle and edge geometries; corner states in graphene can be indicated by the product of Zak phases.
PHYSICAL REVIEW RESEARCH
(2021)
Article
Materials Science, Multidisciplinary
Ren Habara, Katsunori Wakabayashi
Summary: The study investigates the spin-dependent optical conductivity of monolayer NbSe2 and finds that pure spin Hall current can be generated under light irradiation, which can be enhanced by electron doping and persists at room temperature. This effect could be utilized in designing opt-spintronics devices based on 2D materials.
Article
Chemistry, Multidisciplinary
Anh D. Phan, Vu D. Lam, Katsunori Wakabayashi
Article
Chemistry, Physical
Anh D Phan, Kajetan Koperwas, Marian Paluch, Katsunori Wakabayashi
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2020)
