An Novel Explicit Method to Solve Linear Dispersive Media for Finite Difference Time Domain Scheme

A convolution quadrature method for Maxwell's equations in dispersive media

We study the systematic numerical approximation of Maxwell's equations in dispersive media. Two discretization strategies are considered, one based on a traditional leapfrog time integration method and the other based on convolution quadrature. The two schemes are proven to be equivalent and to preserve the underlying energy-dissipation structure of the problem. The second approach, however, is independent of the number of internal states and allows to handle rather general dispersive materials. Using ideas of fast-and-oblivious convolution quadrature, the method can be implemented efficiently…

色散介质的定量OCT重建

Quantitative OCT reconstructions for dispersive media

本文研究从频域OCT测量中重建多层色散介质位置和时变光学性质的一维逆问题，提出以非色散迭代方案为核心的算法，并处理相位恢复与吸收介质情形。

On the time-domain full waveform inversion for time-dissipative and dispersive poroelastic media

This paper concerns the Time-Domain Full Waveform Inversion (FWI) for dispersive and dissipative poroelastic materials. The forward problem is an initial boundary value problem (IBVP) of the poroelastic equations with a memory term; the FWI is formulated as a minimization problem of a least-square misfit function with the (IBVP) as the constraint. In this paper, we derive the adjoint problem of this minimization problem, whose solution can be applied to computed the direction of steepest descent in the iterative process for minimization. The adjoint problem has a similar numerical structure as…

Computation of scattering resonances in absorptive and dispersive media with applications to metal-dielectric nano-structures

In this paper we consider scattering resonance computations in optics when the resonators consist of frequency dependent and lossy materials, such as metals at optical frequencies. The proposed computational approach combines a novel $hp$-FEM strategy, based on dispersion analysis for complex frequencies, with a fast implementation of the nonlinear eigenvalue solver NLEIGS. Numerical computations illustrate that the pre-asymptotic phase is significantly reduced compared to standard uniform $h$ and $p$ strategies. Moreover, the efficiency grows with the refractive index contrast, which makes th…

Time-Domain Analysis of Left-Handed Materials Based on a Dispersive Meshless Method with PML Absorbing Boundary Condition

In this paper, we have proposed a dispersive formulation of scalar-based meshless method for time-domain analysis of electromagnetic wave propagation through left-handed (LH) materials. Moreover, we have incorporated Berenger's perfectly matched layer (PML) absorbing boundary condition (ABC) into the dispersive formulation to truncate open-domain structures. In general, the LH medium as a kind of dispersive media can be described by frequency-dependent constitutive parameters. The most appropriate numerical techniques for analysis of LH media are dispersive formulations of conventional numeric…

一种用于设计Maxwell方程在Havriliak-Negami色散介质中能量衰减保持方案的Pick函数方法

A Pick function approach for designing energy-decay preserving schemes of the Maxwell equations in Havriliak-Negami dispersive media

本文提出基于Pick函数的高阶能量衰减方案，用于Havriliak-Negami色散介质中的Maxwell方程，解决了传统方法无法生成高阶完全单调序列的问题。