Article
Astronomy & Astrophysics
Weitao Liu
Summary: In this work, the structure of the QED spacetime lattice is analyzed, and the Schwinger pair creation process is reviewed from a thermodynamic perspective. This viewpoint allows for the calculation of dynamical mean-field for 3 + 1-dimensional Schwinger pair creation with backreaction. Using a finite volume with external electric fields turned on at t = 0 as an example, the numerical results demonstrate how the backreaction responds to the external fields and influences pair creation.
Article
Multidisciplinary Sciences
Jose Navarro-Salas, Silvia Pla
Summary: We study the particle creation process in the Schwinger model with an external classical source and prove the validity of the semiclassical approach through a comparison with the quantized model. Our discussion also suggests the possibility of using a similar analysis for the massive Schwinger model.
Article
Materials Science, Multidisciplinary
Lars Klemeyer, Hun Park, Jiaxing Huang
Summary: The thermal reduction process of graphene oxide (GO) solids varies depending on their geometry, affecting the properties and stability of the resulting graphene materials. The study enriches the understanding of GO materials and provides insights for tuning the thermal reduction process to achieve high-performance engineering graphene materials.
ACS MATERIALS LETTERS
(2021)
Article
Chemistry, Physical
Fanfan Chen, Nagendra Athreya, Chunxiao Zhao, Mingye Xiong, Haojing Tan, Jean-Pierre Leburton, Jiandong Feng
Summary: Gating in ion transport plays a crucial role in vital living-substancetransmission processes. However, the understanding of subcontinuum ion transport in subnanometer nanopores is still limited. In this study, we report the ion density-dependent dynamic conductance switching process in biomimetic graphene nanopores and explain the phenomenon by a reversible ion absorption mechanism.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2022)
Article
Physics, Applied
Peina Zhang, Xinlu Li, Jianting Dong, Meng Zhu, Fanxing Zheng, Jia Zhang
Summary: Carbon-based magnetic nanostructures have long spin coherent length and potential applications in spintronics. Recent experiments demonstrate that a pair of substitutional boron atoms doped graphene nanoribbons exhibit intrinsic magnetism. In this work, the magnetism is found to be contributed by pi-electrons and the spin-dependent transport properties are investigated.
APPLIED PHYSICS LETTERS
(2022)
Article
Nanoscience & Nanotechnology
G. Giavaras
Summary: In monolayer graphene, an extra node can be created in a quantum state when its eigenenergy varies relative to the energy range of an applied potential well. This node creation is not followed by a change in the eigenenergy index, unlike non-relativistic quantum states. By increasing the strength of the potential well and tuning the magnetic field, an extra node can be created or destroyed in one component. The sign of the angular momentum plays a crucial role in the effect of the node on the quantum states.
PHYSICA E-LOW-DIMENSIONAL SYSTEMS & NANOSTRUCTURES
(2022)
Article
Materials Science, Multidisciplinary
Gaia Forghieri, Paolo Bordone, Andrea Bertoni
Summary: Graphene nanoribbons serve as an ideal platform for electronic interferometry in the integer quantum Hall regime. By solving the time-dependent Schrodinger equation for single carriers in graphene, the study reveals the effects of carrier localization on their transport characteristics in pn junctions. Two types of Mach-Zender interferometers are simulated, showing expected and unexpected phenomena.
Article
Astronomy & Astrophysics
Moaathe Belhaj Ahmed, David Kubiznak, Robert B. Mann
Summary: An isolated critical point refers to a unique thermodynamic critical point in higher dimensions of Kth-order Lovelock gravity with hyperbolic black holes, achieved by fine-tuning Lovelock coupling constants. It represents the merging of two swallowtails and exhibits unconventional critical exponents. By applying a recent proposal for topological charge assignment to thermodynamic critical points, the isolated critical point is suggested to indicate the onset of a topological phase transition of a vortex-antivortex pair.
Article
Physics, Multidisciplinary
Fengshan Zheng, Nikolai S. Kiselev, Luyan Yang, Vladyslav M. Kuchkin, Filipp N. Rybakov, Stefan Bluegel, Rafal E. Dunin-Borkowski
Summary: The creation and annihilation of magnetic solitons, specifically skyrmion-antiskyrmion pairs, have been observed in an exceptionally thin film of a cubic chiral magnet, providing new insights into the behavior of particles and antiparticles in magnetic solids.
Article
Astronomy & Astrophysics
D. D. Su, Y. T. Li, Q. Su, R. Grobe
Summary: In this study, numerical solutions to the Dirac equation are used to investigate the influence of energy shifts on the energy spectrum of created positrons in the laser-induced electron-positron pair-creation process with a highly charged model nucleus. The results suggest that including field-induced energy level shifts is crucial for predicting correct positron energy spectra, especially when the laser intensity allows for electron capture by the nucleus. Additionally, when the laser frequency is tuned to bound state energy differences, coherence from possible electronic Rabi oscillations is transferred to the generated positrons, resulting in new split peaks in their energy spectrum.
Article
Astronomy & Astrophysics
Jens Boos, Valeri P. Frolov, Andrei Zelnikov
Summary: The paper analyzes the Bogoliubov coefficients and spectrum of created particles in a local quantum theory of a scalar field interacting with a delta-shaped time-dependent potential. It then explores how these considerations are influenced by nonlocality when generalized to a specific nonlocal infinite-derivative quantum theory. In this model, nonlocality results in significant resonant amplification of certain modes, affecting both the particle spectrum and total number density of created particles.
Article
Astronomy & Astrophysics
S. Tang, B. King
Summary: The effect of the pulse envelope on electron-positron pair creation in a circularly polarized laser pulse is investigated, with interference and smoothness influencing the pair spectrum. By comparing pair yields in different pulse shapes, a link between pulse shape and photon-polarized Breit-Wheeler pair creation is found. In the transverse momentum distribution, a signal of pulse envelope interference is discovered, showing azimuthal asymmetry in intense fields and long pulses.
Article
Materials Science, Multidisciplinary
P. O. Sukhachov, E. Gorbar
Summary: The hydrodynamic flow of electrons driven by an oscillating electric field in Dirac and Weyl semimetals reveals a double-peak profile of the electric current in a stray magnetic field, influenced by the interplay of viscous, inertial properties, and boundary conditions. This double-peak profile is stable across different sample geometries and insensitive to the specific form of the time dependence of the oscillating electric field. Nozzles and cavities are shown to efficiently enhance or reduce fluid velocity locally.
Article
Astronomy & Astrophysics
Patrick Copinger, Pablo Morales
Summary: This study analyzes the Schwinger pair production in a Belavin, Polyakov, Schwarz and Tyupkin instanton background and its complex extension. The non-Abelian extension of the worldline instanton method is used, showing that while pair production is not predicted in the BPST instanton, a complex extension of it decays via the Schwinger effect.
Article
Multidisciplinary Sciences
Z. B. Tan, A. Laitinen, N. S. Kirsanov, A. Galda, V. M. Vinokur, M. Haque, A. Savin, D. S. Golubev, G. B. Lesovik, P. J. Hakonen
Summary: The non-local Seebeck effect has been observed in a graphene-based Cooper pair splitting device, offering a potential tool for producing entangled electrons. This phenomenon arises from the interplay of non-local Cooper pair splitting and elastic co-tunneling in normal metal-superconductor-normal metal structures.
NATURE COMMUNICATIONS
(2021)