Article
Chemistry, Physical
Anderson Soares da Costa Azevedo, Aldilene Saraiva-Souza, Vincent Meunier, Eduardo Costa Girao
Summary: The theoretical analysis based on density functional theory investigates the microscopic origins of emerging electronic and magnetic properties in quasi-1D nitrogen-rich graphene nanoribbons with chevron-like configurations. It is found that these structures exhibit a broader set of electronic and magnetic behaviors compared to their pure hydrocarbon counterparts, allowing for the strategic engineering of the electronic band gap through different spin configurations and positions of the substituting nitrogen atoms.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2021)
Article
Materials Science, Multidisciplinary
L. F. Man, W. Xu, Y. M. Xiao, H. Wen, L. Ding, B. Van Duppen, F. M. Peeters
Summary: The discovery of hydrodynamic electron liquid (HEL) in graphene has led to the investigation of terahertz (THz) magneto-optical (MO) properties, where the viscous effect can significantly weaken the MO effects such as cyclotron resonance and Faraday rotation. The magnetoplasmons of graphene HEL are affected by the viscous effect, resulting in red-shifts of the magnetoplasmon frequencies. The viscosity in graphene HEL is predicted to strongly affect the magneto-optical and magnetoplasmonic properties, which can be experimentally verified.
Article
Chemistry, Physical
V Bayev, M. Rybin, I Svito, J. Przewoznik, Cz Kapusta, J. Kasiuk, S. Vorobyova, A. Konakov, E. Obraztsova
Summary: This paper discusses the charge transport in a sandwich-like structure composed of monolayer graphene, cobalt nanoparticles, and another layer of graphene. The top graphene layer plays a predominant role in charge transport, exhibiting increased carrier mobility and magnetoresistive effect compared to pristine graphene. This technology shows promise for potential optoelectronic and magneto-optical applications.
APPLIED SURFACE SCIENCE
(2022)
Article
Materials Science, Multidisciplinary
S. Azar Oliaei Motlagh, Vadym Apalkov
Summary: The interaction between graphene quantum dots (GQDs) and ultrashort strong optical pulses was studied theoretically. The absorbance of GQDs has a highly nonlinear dependence on the field amplitude, showing different relationships at small and large-field amplitudes. The absorbance also has a maximum value depending on the size of the dot as the field amplitude changes.
Article
Multidisciplinary Sciences
Golnaz Khanlar, Sahar Izadi Vishkayi, Hamid Rahimpour Soleimani
Summary: The spin filtering junctions composed of graphene and silicon carbide nanoribbons exhibit enhanced electrical and spin conductances, with vacancy defects contributing to the improved spin-filtering effect. The considered junctions display characteristics of a half-metal with reduced thermal conductance, making them suitable for spin-dependent thermoelectric devices. This research predicts the promising potential of the junctions for application in spintronic devices.
SCIENTIFIC REPORTS
(2021)
Article
Chemistry, Physical
Wei Li, Jinlei Wei, Baoan Bian, Bin Liao, Guoliang Wang
Summary: The electronic transport properties of in-plane graphene/MoS2/graphene heterojunctions were studied, showing that different covalent bond connections result in different electron distributions, with the C-S structure exhibiting superior electron transfer properties. Effective doping methods were found to reduce Schottky-barrier height and contact resistance, leading to rectification and linear characteristics in current-voltage curves under bias, in agreement with experimental reports and providing insights for high-performance device design.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2021)
Article
Chemistry, Physical
E. A. Chernova, D. I. Petukhov, A. P. Chumakov, A. V. Kirianova, I. S. Sadilov, O. O. Kapitanova, O. V. Boytsova, R. G. Valeev, S. V. Roth, Ar A. Eliseev, An A. Eliseev
Summary: This study reports on gas and vapor transport properties of ultra-thin graphene oxide membranes with different C:O ratios. It was found that a decrease in C:O ratio leads to an increase in water vapor permeance and a slight reduction in permeance towards permanent gases. Experimental and modeling results show the decisive role of H2O diffusivity in GO membranes.
Article
Materials Science, Multidisciplinary
Diana Slawig, Leo Rizzi, Tom Rothe, Jorg Schuster, Christoph Tegenkamp
Summary: This study analyzed nanographite-based materials using a combination of experimental analysis, including 4-point probe STM and simulation, to provide a comprehensive understanding of microscopic and macroscopic properties. The experimental results determined the full macroscopic conductivity tensor, and microstructural simulations mapped these macroscopic properties to the microscopic building blocks of the sample. By combining these approaches, a coherent and comprehensive description of the electrical material parameters across various length scales was presented.
JOURNAL OF MATERIALS SCIENCE
(2021)
Article
Chemistry, Multidisciplinary
Junjie Chen, Lingyu Meng
Summary: This study investigates thermally rectifying materials and graphene-based nanostructure thermal rectifiers for controlling heat flux. The results show that nanoscale systems can asymmetrically conduct heat, with a maximum rectification coefficient of about 70%.
Article
Chemistry, Multidisciplinary
Junjie Chen, Lingyu Meng
Summary: Graphene-based nanomaterials have important applications in thermal rectification, and defects can be used to modulate the temperature dependence of thermal conductivity. A simplified computational method has been developed to determine the rectification coefficient, and structure factors play a noticeable role in the thermal rectification properties.
Article
Chemistry, Physical
Markus Gruschwitz, Chitran Ghosal, Ting-Hsuan Shen, Susanne Wolff, Thomas Seyller, Christoph Tegenkamp
Summary: Intercalation of Pb on epitaxial graphene using buffer layers on 6H-SiC substrate was studied to achieve large-area intercalation, forming a striped phase structure and providing high conductivity. However, a metal-insulator transition was observed at low temperatures, possibly due to the formation of minigaps induced by static distortion of graphene following the corrugation of the interface layer.
Review
Materials Science, Multidisciplinary
Erwen Zhang, Fanrong Lin, Zhihao Lei, Shuai Qi, Siyuan Ban, Ajayan Vinu, Jiabao Yi, Yanpeng Liu
Summary: Twisted graphene-based homo- and heterostructures, with a unique twist angle-dependent electronic properties, have attracted increasing interest in the research community. This novel twist-angle degree of freedom enables in-depth exploration of quantum phases of matter and intense observation of strongly correlated phenomena.
Article
Multidisciplinary Sciences
J. A. Briones-Torres, R. Perez-Alvarez, S. Molina-Valdovinos, I. Rodriguez-Vargas
Summary: The study investigates the thermoelectric properties of bilayer graphene barrier structures, analyzing the temperature dependence of various parameters like Seebeck coefficient and efficiency. It finds that system resonances play a crucial role in shaping the thermoelectric response.
SCIENTIFIC REPORTS
(2021)
Article
Construction & Building Technology
Chandra Sekhar Reddy Indukuri, Ruben Nerella
Summary: This study aimed to evaluate the transport properties of a cement composite incorporated with graphene oxide (GO). The experimental results demonstrated that the addition of GO could significantly decrease water absorption, chloride migration coefficient, and chloride penetration depth in the cement composite specimens, while improving mechanical properties such as flexural strength and compressive strength. SEM analysis also showed that GO-cement composite specimens had a pore-filled structure. Overall, the incorporation of graphene oxide nano material effectively improved the transport properties of the cement composite.
JOURNAL OF BUILDING ENGINEERING
(2021)
Article
Chemistry, Multidisciplinary
Nicola Pinto, Benjamin McNaughton, Marco Minicucci, Milorad V. Milosevic, Andrea Perali
Summary: The study investigates the morpho-structural properties and charge conduction mechanisms of a low-density graphene sponge with a high carbon to oxygen ratio. The high defect density leads to an insulating electrical behavior at low temperatures, dominated by 2D-VRH conduction. The resistance tends to saturate below 20 K, indicating temperature-independent quantum tunnelling.
Article
Multidisciplinary Sciences
A. T. Costa, P. A. D. Goncalves, D. N. Basov, Frank H. L. Koppens, N. Asger Mortensen, N. M. R. Peres
Summary: The Higgs mode of a superconductor, difficult to observe by far-field optics, can be clearly visible using near-field optics and ultraconfined graphene plasmons. The coupling to the Higgs mode is clearly visible in both cases of graphene plasmons and quantum emitters, offering experimental knobs for studying the electrodynamics of superconductors.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2021)
Article
Education, Scientific Disciplines
J. C. G. Henriques, Thomas G. Pedersen, N. M. R. Peres
Summary: This paper investigates the ionization rate and Stark shift of a one-dimensional model of the H-2(+) ion, solving a complex eigenvalue problem numerically and analytically. The study shows that the ionization rate is highly sensitive to small changes in the external electrostatic field, and saturates at large internuclear distances. The Stark shift is also computed, with comparison to results from other authors using more sophisticated methods.
EUROPEAN JOURNAL OF PHYSICS
(2021)
Article
Optics
J. C. G. Henriques, M. F. C. Martins Quintela, N. M. R. Peres
Summary: In this paper, a method for studying the polarizability due to transitions between exciton states in transition metal dichalcogenides is presented. The excitation of 2(p) dark states, which are not observable in absorption experiments but can be excited in pump-probe experiments, is described. An example of 2(p) dark states in WSe2 is used to demonstrate good agreement between recent experimental measurements and theoretical calculations.
JOURNAL OF THE OPTICAL SOCIETY OF AMERICA B-OPTICAL PHYSICS
(2021)
Article
Physics, Condensed Matter
A. T. Costa, N. M. R. Peres
Summary: The close proximity between graphene sheets and monolayers of 2D superconductors can lead to hybridization between their collective excitations. Heterostructures formed by combinations of graphene sheets and 2D superconductor monolayers show distinct features on the near-field reflection coefficient that can be observed in scanning near-field microscopy experiments, providing a promising platform for probing the many-body physics of superconductors.
JOURNAL OF PHYSICS-CONDENSED MATTER
(2022)
Article
Physics, Condensed Matter
J. C. G. Henriques, T. V. C. Antao, N. M. R. Peres
Summary: This paper investigates a honeycomb antiferromagnet under the influence of an external laser field. It is found that the external laser modifies the exchange interaction between spin operators and induces a Dzyaloshinskii-Moria interaction between second neighbors. The study shows that the eigen-excitations of the system can be controlled by the laser and can couple with cavity photons.
JOURNAL OF PHYSICS-CONDENSED MATTER
(2022)
Article
Physics, Condensed Matter
Mauricio F. C. Martins Quintela, Joao C. G. Henriques, Luiz G. M. Tenorio, Nuno M. R. Peres
Summary: This Perspective article introduces several theoretical methods for determining exciton wave functions and eigenenergies. These methods include analytical, semianalytical, and numeric approaches. The article provides explicit details on each method, allowing newcomers to conduct their own research without facing a steep learning curve. The article begins with a variational method and concludes with a simple semianalytical approach for solving the Bethe-Salpeter equation in gapped 2D materials.
PHYSICA STATUS SOLIDI B-BASIC SOLID STATE PHYSICS
(2022)
Article
Chemistry, Multidisciplinary
Aline dos Santos Almeida, Dario A. Bahamon, Nuno M. R. Peres, Christiano J. S. de Matos
Summary: The use of graphene in surface plasmon resonance sensors has advantages such as protecting the film and increasing sensitivity. However, the role of single and few layers of graphene in sensitivity enhancement was critically examined, and it was found that only the isotropic layer model provides significant sensitivity increases.
Article
Chemistry, Multidisciplinary
Mauricio F. C. Martins Quintela, Nuno M. R. Peres
Summary: This paper investigates the scattering phenomenon of excitons by free carriers in monolayer hexagonal boron nitride. The excitonic states are described using variational wave functions, and the distinction between elastic and inelastic scattering is made. The contribution of free carrier scattering to the excitonic linewidth is analyzed in terms of temperature and carrier density dependence.
APPLIED SCIENCES-BASEL
(2022)
Article
Physics, Condensed Matter
M. F. C. Martins Quintela, A. T. Costa, N. M. R. Peres
Summary: This study explores the properties of excitons in transition-metal dichalcogenide monolayers lacking inversion symmetry. It is found that exciton binding energies can be larger than the electronic band gap, making these materials promising candidates for the exciton insulator phase.
JOURNAL OF PHYSICS-CONDENSED MATTER
(2022)
Editorial Material
Education, Scientific Disciplines
T. V. C. Antao, N. M. R. Peres
EUROPEAN JOURNAL OF PHYSICS
(2023)
Article
Physics, Condensed Matter
M. F. C. Martins Quintela, N. M. R. Peres
Summary: This paper investigates the behavior of Wannier excitons in hexagonal boron nitride quantum dots, examining the influence of quantum dot dimensions on the excitonic states.
JOURNAL OF PHYSICS-CONDENSED MATTER
(2023)
Article
Chemistry, Multidisciplinary
A. T. Costa, Mikhail I. Vasilevskiy, J. Fernandez-Rossier, Nuno M. R. Peres
Summary: This article investigates the challenges of forming hybrid plasmon-magnon polaritons in heterostructures and demonstrates the possibility of polaritons formed by graphene plasmons and magnons in two-dimensional ferromagnetic insulators.
Article
Materials Science, Multidisciplinary
M. F. C. Martins Quintela, N. M. R. Peres
Summary: This paper investigates the opening of band gap and excitonic optical response in rhombohedral trilayer graphene under external electric field. The study reveals that the excitonic resonances can be tuned by the electric field, leading to increased localization of excitonic states.
Article
Materials Science, Multidisciplinary
J. C. G. Henriques, Itai Epstein, N. M. R. Peres
Summary: This paper explores the excitonic optical response of biased bilayer graphene using a combination of tight-binding model and the solution of the Bethe-Salpeter equation. The optical selection rules are obtained analytically, followed by the calculation of the absorption spectrum of a biased bilayer encapsulated in hexagonal boron nitride. The theoretical prediction shows excellent agreement with experimental data.
Article
Materials Science, Multidisciplinary
J. C. G. Henriques, B. Amorim, R. M. Ribeiro, N. M. R. Peres
Summary: This paper discusses the optical response resulting from excitonic effect in two types of hBN bilayers: AB and AA'. By converting the four-band Bethe-Salpeter equation into a one-dimensional problem, the numerical burden of calculation is significantly reduced. The study of these bilayers is crucial for understanding twisted bilayers at arbitrary angles.
