Article
Mathematics, Applied
Tingchun Wang, Tingfeng Wang
Summary: This paper investigates two finite difference schemes for numerically solving the coupled Gross-Pitaevskii equations with angular momentum rotation terms. The schemes are proven to be uniquely solvable and conserve mass and energy in a discrete sense. The paper introduces the 'cut-off' function technique and inductive argument to establish optimal error estimates without specific requirements on the grid-ratio or initial values. Numerical results confirm the convergence order of the schemes to be O(tau 2 + h2), where tau is the time-step and h is the mesh size.
JOURNAL OF COMPUTATIONAL AND APPLIED MATHEMATICS
(2023)
Article
Physics, Applied
Zicun Li, Jinbin Li, Daning Shi
Summary: In this study, the circularly-symmetric phase separation in a spin-1 spin-orbit angular momentum coupled Rb-87 Bose-Einstein condensate (BEC) system was investigated using numerical solutions. The increase of the coupling strength resulted in the formation of annular structures, which exhibited different characteristics compared to the phase separation of a spin and linear momentum coupled BEC. The experimental results supported the findings, and the influence of different parameters on the system was analyzed.
MODERN PHYSICS LETTERS B
(2022)
Article
Mathematics, Applied
Jianfeng Liu, Qinglin Tang, Tingchun Wang
Summary: This article focuses on the numerical study of a coupled system of Gross-Pitaevskii equations that describes spin-orbit-coupled Bose-Einstein condensates. The article proposes an implicit finite difference scheme that is proven to be uniquely solvable and conserves mass and energy in the discrete sense. The scheme is also shown to be stable and convergent at a rate of O(h(2)+t(2)) in the maximum norm, without any grid-ratio restriction. Previous works often required grid ratio restrictions and provided error estimates in discrete L-2 norm or H-1 norm, which could not imply the maximum error estimate. Numerical results highlight the error estimate, conservation laws, and investigate various dynamics of the coupled Gross-Pitaevskii equations.
NUMERICAL METHODS FOR PARTIAL DIFFERENTIAL EQUATIONS
(2023)
Article
Multidisciplinary Sciences
Fan Nan, Xiao Li, Shuailong Zhang, Jack Ng, Zijie Yan
Summary: This study reports the stable optical trapping and switchable optical rotation of nanoparticle-assembled micromotors with programmed phase of light. By imprinting customized phase gradients into a circularly polarized flat-top laser beam, the researchers were able to trap and assemble metal nanoparticles into reconfigurable clusters, allowing for direction-switchable and magnitude-tunable optical torque.
Article
Mathematics, Applied
Huaijun Yang, Dongyang Shi
Summary: This paper focuses on the unconditional optimal error analysis of a linearized, decoupled and conservative Galerkin finite element method for the Klein-Gordon-Schrodinger equations. The contributions of this work include proving the mass and energy conservation properties of the scheme, deriving the a priori boundedness of the numerical solutions, and developing a novel approach that avoids the use of error splitting technique and the restrictions between time step size and mesh size. Numerical results are provided to confirm the theoretical analysis and demonstrate the efficiency of the proposed scheme.
COMMUNICATIONS IN NONLINEAR SCIENCE AND NUMERICAL SIMULATION
(2023)
Article
Physics, Applied
Qiao Jiang, Hong Xiang, Dezhuan Han
Summary: This study proposes a method to design a plasmonic metasurface that can control the generation and superposition of surface plasmon polariton (SPP) vortices, demonstrating that the superposition of SPP vortices can be accurately controlled by the polarization states of the incidence, providing a feasible way to design miniaturized photonic devices.
APPLIED PHYSICS LETTERS
(2021)
Article
Chemistry, Physical
Benjamin L. Augenbraun, Sean Burchesky, Andrew Winnicki, John M. Doyle
Summary: This study presents a detailed laser spectroscopic study on the transitions of calcium(I) phenoxide. The rotational band systems are analyzed, and the structure of calcium monophenoxide is compared to other calcium radicals. This work shows the potential application of functionalizing aromatic molecules for laser-based control.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2022)
Article
Physics, Applied
Kaixiang Cheng, Zexu Liu, Zheng-Da Hu, Guoyang Cao, Jingjing Wu, Jicheng Wang
Summary: This study demonstrates an all-dielectric metasurface based on a geometric phase for generating perfect vortex (PV) beams with different topological charges. The metasurface, which is ultra-thin and flexible, has the potential for a wide range of applications in manipulating circularly polarized light.
APPLIED PHYSICS LETTERS
(2022)
Article
Optics
Guan Gui, Nathan J. Brooks, Henry C. Kapteyn, Margaret M. Murnane, Chen-Ting Liao
Summary: The study observes the second-harmonic spatiotemporal orbital angular momentum of an optical pulse and reveals the conservation of topological charge during frequency doubling. The experiment suggests a general nonlinear scaling rule for ST-OAM, analogous to conventional OAM of light, and demonstrates that the topology of a second-harmonic ST-OAM pulse can be modified by complex spatiotemporal astigmatism.
Article
Nanoscience & Nanotechnology
Xiaofei Wu, Raphael Ehehalt, Gary Razinskas, Thorsten Feichtner, Jin Qin, Bert Hecht
Summary: Researchers have successfully demonstrated the remote control of microscopic robots in two dimensions in all three degrees of freedom using unfocused light and plasmonic nanoantennas. This breakthrough has potential applications in transport, manipulation, and sensing of nano and mesoscale objects.
NATURE NANOTECHNOLOGY
(2022)
Article
Mathematics, Interdisciplinary Applications
Liangwei Dong, Zhijing Du, Zhijun Ren
Summary: This paper predicts the existence of vortex solitons with one and two off-centered phase singularities in competing media trapped in a rotating harmonic potential. The rotation of external potentials shifts the singularity position and affects the angular momentum carried by each photon. The study also finds that rotating asymmetric vortex states carrying fractional angular momentum are extremely robust under high power conditions.
CHAOS SOLITONS & FRACTALS
(2023)
Article
Mathematics
Sergey Ershkov, Dmytro Leshchenko
Summary: We propose a novel model for the dynamics of non-rigid asteroid rotation by using the added mass model to describe the response of a 'rubble pile' volumetric material. In this model, an inelastic collision causes the formation of a solidified plug in the crater, which is then pushed outside the asteroid's surface by centrifugal forces, creating a secondary rotating companion. The rotational dynamics of the asteroid are altered due to the decrease in mass, in accordance with the law of angular momentum conservation. Additionally, we present a semi-analytical estimation method for calculating the mass of the solidified plug, taking into account the long-term dissipation of kinetic energy.
Article
Physics, Multidisciplinary
Sajad Aghapour, Lars Andersson, Kjell Rosquist
Summary: This paper introduces a novel conserved Lorentz covariant tensor, the helicity tensor, in Maxwell theory, demonstrating its role and characteristics in conservation laws. The Lorentz covariance of the helicity tensor contrasts with previous formulations of the helicity hierarchy, proving its emergence as a Noether current for a varational symmetry of a duality-symmetric Lagrangian.
Article
Optics
Yao Zhang, Keming Pan, Jia Xu, Weiting Zhu, Daomu Zhao
Summary: The study focused on a family of ATVGSM beams derived from the coupling of off-axis vortex phase and twist phase, carrying orbital angular momentum and being influenced by the state of coherence. During propagation, the beam exhibited a rotating crescent shape, with stability affected by phase interaction and twist strength. Coherence vortices with opposite topological charge were generated in pairs and moved along specific trajectories under various conditions, contributing to the rotating properties of the intensity pattern.
OPTICS COMMUNICATIONS
(2021)
Article
Multidisciplinary Sciences
Ludovic Petitdemange, Florence Marcotte, Christophe Gissinger
Summary: The evolution of stars is influenced by internal rotation dynamics, but the mechanisms involved are not well understood. Magnetic fields may play a role in transporting angular momentum and chemical elements, but the origin of magnetism in radiative stellar layers is unclear. Through numerical simulations, we identified a subcritical transition from laminar flow to turbulence caused by a magnetic dynamo. This mechanism could produce strong magnetic fields inside radiative stars that are not observable on their surface.
