Article
Computer Science, Interdisciplinary Applications
Niloo Misaghian, Mehrez Agnaou, Mohammad Amin Sadeghi, Hamed Fathiannasab, Isma Hadji, Edward Roberts, Jeff Gostick
Summary: This study develops a deep learning framework to accurately predict the diffusive conductance in porous media by analyzing 3D images of pore regions extracted from tomograms. The results demonstrate high accuracy and significantly improved prediction speed.
COMPUTERS & GEOSCIENCES
(2022)
Article
Physics, Applied
Weijun Zeng, Kirsi Tappura, Masahiro Kamada, Antti Laitinen, Heikki Seppa, Pertti Hakonen
Summary: Recent experiments have shown that mobility fluctuations impact 1/f noise in two-dimensional conductors. This study investigates the second spectrum of noise caused by mobile impurities on a two-dimensional lattice through simulations and experiments. The simulations reveal a 1/f^d behavior with an exponent of d≈0.8±0.15, while the experiments on suspended graphene yield an exponent of d≈0.7±0.3, independent of the amount of adsorbed atoms.
APPLIED PHYSICS LETTERS
(2023)
Article
Materials Science, Multidisciplinary
Shiang-Bin Chiu, Alina Mrenca-Kolasinska, Ka Long Lei, Ching-Hung Chiu, Wun-Hao Kang, Szu-Chao Chen, Ming-Hao Liu
Summary: Graphene, with its similar dispersion relation to photons, has great potential for applications in electron optics. By varying the carrier density with external gates, it is possible to create electron waveguides similar to optical fibers, and by confining the carriers in bipolar junctions, transverse guiding modes can be formed. Waveguides created by gating graphene with carbon nanotubes (CNTs) can produce sharp conductance plateaus and have potential applications in Aharonov-Bohm and two-path interferometers, as well as carrier injection in graphene. The versatility of CNT-induced waveguides allows for various possibilities in manipulating electrons in graphene-based devices.
Article
Physics, Applied
Cecilia Herrero, Laurent Joly, Samy Merabia
Summary: This paper investigates the interfacial heat transfer between water and gold and proposes a method to increase the interfacial resistance by nanostructuring the gold surface and coating it with graphene. The results show a significant increase in the resistance compared to the planar gold situation. The predicted high thermal resistance makes this system a robust alternative to superhydrophobic materials.
APPLIED PHYSICS LETTERS
(2022)
Article
Mathematics, Applied
Zehba Raizah, Hussam Alrabaiah, Anwar Saeed, Asif Ullah Hayat, Ahmed M. Galal, Poom Kumam
Summary: This study provides a comprehensive assessment of three-dimensional Jeffery fluid flow under the significances of thermal radiation and magnetohydrodynamics. The results revealed that the motion of the Jeffery fluid decreases with increasing porosity term but increases with the rising influence of wall thickness factor. The velocity curve decreases in both x and y directions with the increasing values of Darcy-Forchheimer and magnetic field factors. Furthermore, the temperature curve intensifies with the addition of porosity factor and Deborah number, while lessens with the rising influence of power index.
ZAMM-ZEITSCHRIFT FUR ANGEWANDTE MATHEMATIK UND MECHANIK
(2023)
Article
Materials Science, Multidisciplinary
Adam Rycerz, Piotr Witkowski
Summary: This paper investigates the charge transport characteristics of ballistic graphene samples in a multimode regime. It is found that the conductance is reduced by a factor of pi/4 compared to standard Sharvin contacts in two-dimensional electron gas, and the shot-noise power is enhanced up to F approximate to 1/8. The study considers the disk-shaped setup in graphene and reveals that the multimode conductance is slightly enhanced for any inner radius smaller than the outer radius. Analytical approximations for the conductance and the Fano factor are derived and compared with exact numerical results. The results show deviations from the standard Sharvin transport characteristics, even though they are closer to the predicted values for the limit where the inner radius is much smaller than the outer radius. The paper also studies the behavior of the system when the electrostatic potential barrier is tuned from rectangular to parabolic shape, demonstrating a crossover from sub-Sharvin to standard Sharvin transport regime. The implications for a finite section of the disk are discussed as well.
Article
Chemistry, Physical
Lais C. Lopes, Adriano Santos, Paulo R. Bueno
Summary: Impedance-derived capacitance spectroscopy is a useful method for measuring and analyzing the conductance and capacitance of a single-layer graphene sheet. Quantum conductance and capacitance exhibit V-shapes when measured under specific conditions, consistent with literature results.
Article
Biochemical Research Methods
Chen Yang, Caiyao Yang, Yilin Guo, Jianfei Feng, Xuefeng Guo
Summary: The ability to measure the behavior of a single molecule during a reaction can uncover dynamic and static disordered states that may not be represented in ensemble averages. This article introduces a method to build devices with graphene-molecule-graphene single-molecule junctions integrated into an electrical circuit. These devices are stable, tolerant to mechanical changes and solution environments, and enable sensitive detection of variations in physical and chemical properties of detected molecules. The on-chip setup of single-molecule junctions also allows for logic functions and analysis of reaction intermediates.
Article
Chemistry, Physical
Huasong Qin, Yan Chen, Yanfei Wu, Maoqing Li, Yilun Liu, Qing-Xiang Pei
Summary: This study systematically investigates the thermal transport behaviors of graphene with topological defect-induced wrinkles through nonequilibrium molecular dynamics simulations. It is found that the wrinkled graphene exhibits lower thermal conductivity due to the phonon scattering enhancement caused by topological defects. The thermal conductivity of wrinkled graphene is insensitive to sample size and temperature. These findings provide a theoretical basis for engineering the thermal conductivity of graphene through topological optimization strategies.
JOURNAL OF PHYSICAL CHEMISTRY C
(2022)
Article
Engineering, Aerospace
Qi Yan, Zhiqiang Wan, Chao Yang
Summary: Flight load calculation is a crucial step in aircraft design and optimization, which involves numerous computations and substantial computing resources. Efficient calculation methods are necessary to shorten research and development cycles while maintaining accuracy.
Article
Materials Science, Multidisciplinary
Jing-Yun Fang, Ning-Xuan Yang, Qing Yan, Ai-Min Guo, Qing-Feng Sun
Summary: The study reveals the presence of dissipation in topological systems, where thermal dissipation can occur in the quantum Hall regime in graphene. Dissipation processes are accompanied by the evolution of energy distribution from nonequilibrium to equilibrium.
Article
Chemistry, Multidisciplinary
Jiahao Lin, Peng Li, Yingjun Liu, Ziqiu Wang, Ya Wang, Xin Ming, Chao Gao, Zhen Xu
Summary: The large size of graphene sheets can lead to negative size effect due to the formation of wrinkles. By using wrinkle engineering strategy, the size predicament can be resolved, leading to ultra-high mechanical strength and superior functionalities of graphene materials. The origin of this size effect highlights the importance of modulating wrinkles in graphene macroscopic materials.
Article
Multidisciplinary Sciences
Alexandr P. Kornev, Phillip C. Aoto, Susan S. Taylor
Summary: The topological analysis of protein residue networks is a useful method for understanding the roles of individual residues. In this study, the researchers used protein kinase A as a study object and found that using local spatial pattern alignment could detect functionally important residues in the protein residue network.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2022)
Article
Chemistry, Physical
Jian Cheng, Sheng Jiang, Feng Xie, Lie Chen, Qibiao Yang, Deyuan Lou, Zhongsheng Zhai, Fengping Li, Dun Liu
Summary: Graphene has excellent electrical and thermal conductivity, making it highly promising for applications in electronic chips and sensors. This paper presents a new method for reducing graphene oxide (GO) using a femtosecond laser from the GO-free side of polyethylene tere-phthalate (PET). The technique achieved one of the lowest sheet resistances of 75 omega/sq in air and demonstrated essential bonding properties for flexible electronics.
APPLIED SURFACE SCIENCE
(2023)
Editorial Material
Biodiversity Conservation
Chris Huntingford, Rebecca J. Oliver
Summary: Ecological research has mainly focused on identifying how different environmental factors restrict photosynthesis, but there is less attention on accurately modeling the transition between limitations as drivers change. Whether these changes are modeled as a single switch or involve an intermediate period of co-limitation can significantly impact estimated levels of photosynthesis.
GLOBAL CHANGE BIOLOGY
(2021)
Article
Physics, Multidisciplinary
A. Donis Vela, G. Lemut, M. J. Pacholski, C. W. J. Beenakker
Summary: The research has shown that introducing s-wave superconductivity in a topological insulator can support chirality inversion of Majorana fermions along the edge with a magnetic insulator, and this inversion can be changed by the counterflow of supercurrent. Furthermore, this chirality inversion leads to a doubling of the thermal conductance in a channel parallel to the supercurrent.
NEW JOURNAL OF PHYSICS
(2021)
Article
Physics, Multidisciplinary
M. J. Pacholski, G. Lemut, O. Ovdat, I Adagideli, C. W. J. Beenakker
Summary: In a Fu-Kane heterostructure, a spatially oscillating pair potential with a redundant vector can lead to a deconfinement transition of Majorana bound states, forming a dispersionless Landau level. The coherent superposition of electrons and holes in the Majorana Landau level can be detected through local density oscillations, and the striped pattern provides a way to measure the chirality of the Majorana fermions.
PHYSICAL REVIEW LETTERS
(2021)
Article
Physics, Multidisciplinary
G. Lemut, M. J. Pacholski, J. Tworzydlo, C. W. J. Beenakker
Summary: We investigate the spectral statistics of a Kramers-Weyl Hamiltonian in a chaotic quantum dot. Despite having symplectic time-reversal symmetry, we observe that for small values of t, the level spacing distribution follows the orthogonal ensemble (beta = 1) instead of the expected symplectic ensemble (beta = 4). We attribute this finding to a supercell symmetry of the Hamiltonian.
JOURNAL OF PHYSICS A-MATHEMATICAL AND THEORETICAL
(2022)
Article
Physics, Condensed Matter
A. Donis Vela, G. Lemut, M. J. Pacholski, J. Tworzydlo, C. W. J. Beenakker
Summary: In an electric field, massless Dirac fermions propagate along the field lines without backscattering, a phenomenon known as 'Klein tunneling'. However, when the Dirac equation is discretized in space and time, this effect may be lost. To address this issue, we propose a staggered space-time lattice discretization method that avoids the spurious breakdown of Klein tunneling caused by fermion doubling.
JOURNAL OF PHYSICS-CONDENSED MATTER
(2022)
Article
Physics, Multidisciplinary
A. Donis Vela, M. J. Pacholski, G. Lemut, G. Tworzydlo, C. W. J. Beenakker
Summary: This study introduces a method to implement Dirac fermions on a space-time lattice, which can avoid the effects of scattering between multiple Dirac cones or singularities at zone boundaries on protecting symmetries. It is found that in the discretization of a single Dirac cone, the discontinuity of the time-evolution operator at Brillouin zone boundaries results in the absence of topological protection.
ANNALEN DER PHYSIK
(2022)
Review
Physics, Multidisciplinary
C. W. J. Beenakker, A. Donis Vela, G. Lemut, M. J. Pacholski, J. Tworzydlo
Summary: This article reviews methods to discretize the Hamiltonian of a topological insulator or superconductor, while preserving the topological protection of massless excitations (Dirac fermions or Majorana fermions). The method of tangent fermions, introduced by Richard Stacey, is highlighted as uniquely suitable for this purpose. Tangent fermions propagate on a 2+1 dimensional lattice with a tangent dispersion, avoiding the fermion doubling lattice error and maintaining the fundamental symmetries of the Dirac Hamiltonian. Although the discretized Hamiltonian is nonlocal, it can be transformed into a generalized eigenproblem that is local in space and time. Applications discussed include Klein tunneling, absence of localization by disorder, anomalous quantum Hall effect, and thermal metal behavior of Majorana fermions.
ANNALEN DER PHYSIK
(2023)
Article
Physics, Multidisciplinary
C. W. J. Beenakker
Summary: A method from random-matrix theory is used to calculate the pair correlation function of a one-dimensional gas of classical particles with a power-law repulsive interaction potential. An integral formula for the covariance of single-particle operators is obtained, which generalizes known results in different limits of the interaction potential. As an application, the variance of the center of mass of the gas is calculated, showing a universal large-N limit.
PHYSICAL REVIEW RESEARCH
(2023)
Article
Physics, Multidisciplinary
Aleksander Sanjuan Ciepielewski, Jakub Tworzydlo, Timo Hyart, Alexander Lau
Summary: In this study, we investigate the relationship between the four-terminal conductance and the Fermi surface topology in mesoscopic, ballistic samples of small-angle twisted bilayer graphene. We establish a correspondence between features in the wide-junction conductance and the presence of Van Hove singularities in the density of states. Additionally, we identify other transport features such as pressure-tunable minimal conductance, conductance peaks coinciding with nonsingular band crossings, and unusually large conductance oscillations as a function of system size.
PHYSICAL REVIEW RESEARCH
(2022)
Article
Materials Science, Multidisciplinary
D. O. Oriekhov, T. T. Osterholt, T. Vakhtel, A. R. Akhmerov, C. W. J. Beenakker
Summary: In this study, we investigate the behavior of electron propagation in a lattice with anisotropic dispersion in the x-y plane. We demonstrate that a point source generates a breathing mode, which periodically spreads and refocuses after propagating for a certain distance. Unlike classical cyclotron radius, this is a quantum mechanical effect.
Article
Materials Science, Multidisciplinary
Maxime Debertolis, Izak Snyman, Serge Florens
Summary: This study presents an efficient and robust algorithm to simulate the electronic correlations induced by dynamical quantum impurities in metals. By using the recursive generation of natural orbitals, the algorithm provides accurate spatial resolution on lattices with tens of thousands of sites and investigates the charge screening cloud in both disordered and clean lattices.
Article
Materials Science, Multidisciplinary
T. Vakhtel, D. O. Oriekhov, C. W. J. Beenakker
Summary: We have identified a mapping between 2D electron transport in a minimally twisted graphene bilayer and a 1D quantum walk, where one spatial dimension acts as time. This mapping allows us to observe Bloch oscillations in purely DC transport as magnetoconductance oscillations with periodicity set by the Bloch frequency.
Article
Materials Science, Multidisciplinary
G. Lemut, M. J. Pacholski, C. W. J. Beenakker
Summary: The study shows that the direction of the magnetic field with respect to the vector separating Weyl points of opposite chirality in a Weyl superconductor affects the electrical conduction.
Article
Materials Science, Multidisciplinary
D. O. Oriekhov, Y. Cheipesh, C. W. J. Beenakker
Summary: We investigate the staircase I-V characteristic generated by Rabi oscillations in a Josephson junction with a resonant level, providing a way to probe the coherence of the qubit. This phenomenon is similar to the Majorana-induced DC Shapiro steps in topological Josephson junctions, but now for a nontopological Andreev qubit.
