Abstract : This mini-symposium is organized to provide a forum for fellow researchers
working on numerical methods for wave propagation problems to present and
discuss their recent advances and achievements. Topics to be covered
include but not limited to: FDTD methods, finite element methods, spectral methods,
multiscale methods, novel techniques for metamaterials and graphene.
[01429] Analysis and simulation of carpet cloak model with metamaterials
Format : Talk at Waseda University
Author(s) :
Jichun Li (University of Nevada Las Vegas)
Abstract : This talk is concerned about a time-domain carpet invisibility cloak model. Here we consider two new finite element schemes to solve it. Stability and optimal error estimates are proved for both schemes. Numerical results are
presented to support our analysis and demonstrate the cloaking phenomenon.
[01639] Edge elements on nonaffine quadrilateral and hexahedral grids for Maxwell eigenproblem
Format : Talk at Waseda University
Author(s) :
HUOYUAN DUAN (Wuhan University, School of Mathematics and Statistics)
Abstract : Most of the edge elements on nonaffine quadrilateral and hexhaedral grids do not satisfy the so-called discrete compactness property. Consequently, they generate spurious eigenmodes and are not spectral correct. We propose some new finite element methods for Maxwell eigenproblems so that all the edge elements on nonaffine quadrilateal and hexhaedral grids are spurious-free and spectral correct. The new methods have been confirmed by theory and numerics.
[01856] Deriving consistent surface fields for compatible FETD discretizations of Maxwell’s equations
Format : Online Talk on Zoom
Author(s) :
Duncan McGregor (Sandia National Laboratories)
Abstract : The coupling of electromagnetic energy to a cable is a critical quantity of interest in some engineering applications. These cables can be modelled as internal boundaries with a perfect electric conductor condition. An intuitive method is a loop integral of the magnetic field around the cable. This leads to physical and mathematical concerns. As such, we use Dirichlet-to-Neumann map to compute surface currents. We will describe our method and present numerical results.
[01860] FDTD Method With Explicit Non-Iterative and Second Order Treatment for Kerr Nonlinearities
Format : Talk at Waseda University
Author(s) :
Jinjie Liu (Delaware State University)
Abstract : In this talk, we introduce a new explicit non-iterative FDTD algorithm for solving Maxwell's equations in nonlinear Kerr media. The FDTD method is a widely used numerical technique for solving Maxwell's equations in complex media. Our method balances accuracy and computational cost, offering similar accuracy to Newton's iterative method but at a lower computational expense. The effectiveness of our method is demonstrated by its quadratic convergence rate, as well as several numerical examples such as simulations of four-wave mixing and soliton propagation.
[02077] Harnessing the Power of Exascale Computing for Microelectronics Modeling
Format : Talk at Waseda University
Author(s) :
Zhi Jackie Yao (Lawrence Berkeley National Lab)
Revathi Jambunathan (Lawrence Berkeley National Lab)
Andy Nonaka (Lawrence Berkeley National Lab)
Prabhat Kumar (Lawrence Berkeley National Lab)
Saurabh Sawant (Lawrence Berkeley National Lab)
Abstract : As the era of Moore's law comes to a close, there has been a surge in the development of microdevices that involve more complex physical interactions than conventional electromagnetic waves and single-phase materials. However, gaining a deeper understanding of these interactions has been hindered by the significant disparity in time and length scales and a lack of effective modeling techniques.
To address these challenges, we have developed ARTEMIS, a scalable simulation tool that harnesses the power of GPU-based supercomputing systems to model next-generation microelectronic devices, including electronic, spintronic, superconducting, and ferroelectric systems. ARTEMIS leverages the developments of two Exascale Computing Projects and supports dispersive material properties, user-defined excitations and boundary conditions, and heterogeneous physical coupling. Specifically, with its micromagnetics module, ARTEMIS is suitable for nonlinear spintronic applications and can be used as a device-level design and optimization tool.
This new approach also provides a path to understanding and developing fully integrated electronic systems that go beyond the capabilities of traditional semiconductor technologies. ARTEMIS will enable a broader exploitation of new materials and provide new mechanisms for everything from low-power computing to high-efficiency microwave components, contributing to the development of next-generation architectures.
[02080] Simulating Time Domain Electromagnetic Waves on a Differentiable Programming Platform
Format : Talk at Waseda University
Author(s) :
Yanyan Hu (University of Houston)
Yuchen Jin (University of Houston)
Xuqing Wu (University of Houston)
Jiefu Chen (University of Houston)
Abstract : A trainable theory-guided recurrent neural network (RNN) equivalent to finite-difference-time-domain (FDTD) method is designed to formulate electromagnetic propagation, solve Maxwell’s equations, and the inverse problem on differentiable programming platform PyTorch. For forward modeling, the computation efficiency is substantially improved. The inverse problem can be solved by setting the trainable weights of RNN as the material-related parameters and network training. Numerical results demonstrate the effectiveness and efficiency of the method for forward and inverse electromagnetic modeling.
[02117] Iterative two-level algorithm for nonsymmetric or indefinite problems
Format : Talk at Waseda University
Author(s) :
Ming Tang (South China Normal University)
Xiaoqing Xing (South China Normal University)
Ying Yang (Guilin University of Electronic Technology)
Liuqiang Zhong (South China Normal University)
Abstract : In this talk, some new iterative two-level algorithms are designed and analyzed for solving the finite element discretization for nonsymmetric or indefinite elliptic/Maxwell problems. The two-level methods use only the same coarse spaces as the traditional two- grid algorithm, but its “fine spaces” use the higher order finite element space under the coarse grid. Therefore, the iterative two-level algorithm only need one grid and achieve the same convergence order of the traditional two-grid algorithms. At last. Numerical experiments are implemented to support the theoretical results, especially, the computational cost of two-level algorithms are lower to achieve the same convergence order for traditional two-grid algorithms.
[01863] Analysis and application of FEMs for Ziolkowski's PML model
Format : Talk at Waseda University
Author(s) :
Li Zhu (Portland State University)
Jichun Li (University of Nevada Las Vegas)
Abstract : Perfectly Matched Layer PML technique is an effective tool proposed by Berenger to solve a wave
propagation problem in unbounded domain without reflections. Here we are interested in the Ziolkowski PML reformulated in an integro-differential form, We introduce two novel FEMs for solving this equivalent PML model. Stability and convergence analysis are established for both schemes. Numerical results are presented to support our analysis and demonstrate the wave absorption effectiveness of this PML.
[02737] Highly Efficient Iterative Method with High Order ABC for Acoustic Scattering
Format : Talk at Waseda University
Author(s) :
Vianey Roman Villamizar (Brigham Young University)
Tahsin Khajah (University of Texas at Tyler)
Jonathan Hale (University of Wisconsin)
Abstract : In this paper, we have developed a highly efficient numerical method for acoustic multiple scattering. This novel method consists of a high order local absorbing boundary condition combined with an isogeometric finite element and finite differences methods. By employing high order NURB basis, a globally high order method results. In our numerical experiments, we obtain errors close to machine precision by appropriate implementation of p- and h-refinement. We include numerical results which demonstrate the improved accuracy and efficiency of this new formulation compared with similar methods.
[02916] The effect normal electric fields on the flow structure beneath waves
Format : Talk at Waseda University
Author(s) :
Roberto Ribeiro Santos Junior (Universidade Federal do Parana)
Marcelo V. Flamarion (Rural Federal University of Pernambuco)
Tao Gao (University of Essex)
Alex Doak (University of Bath)
Abstract : Waves with constant vorticity and electrohydrodynamics flows are two topics in fluid dynamics that have attracted much attention from scientists for both the mathematical challenge and their industrial applications. The coupling of electric fields and vorticity is of significant research interest. In this talk, we present numerical results on the effect of normal electric fields on the flow structure beneath periodic and solitary rotational waves. By using a combination of conformal mapping techniques and pseudo-spectral numerical methods, we show how variations in voltage potential can affect particle trajectories and the pressure within the bulk of the fluid
