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SUMMARY We present a fast time-domain multiphysics simulation framework that combines full-wave electromagnetism (EM) and carrier transport in semiconductor devices (technology computer-aided design (TCAD)) for radio frequency (RF) and mixed-signal modules. The proposed framework features a division of linear and nonlinear components in the EM–TCAD coupled system. The linear portion is extracted and handled independently with high efficiency by a matrix exponential approach assisted with Krylov subspace method. The nonlinear component is treated by ordinary Newton's method yet with a much sparser Jacobian matrix that leads to substantial speedup in solving the linear system of equations. More convenient error management and adaptive control are also available through the linear and nonlinear decoupling. Furthermore, a new form of system formulation is developed to further enhance the efficiency of the proposed framework by reducing the stiffness of EM–TCAD systems via special equation and variable transforms. Copyright © 2015 John Wiley & Sons, Ltd.

Helmholtz decomposition (HD) is a vector analysis fundamental tool and plays an important role in electromagnetics (EM) and microwave engineering. Instead of applying HD to the EM solving process, this article proposes an integral equation based rigorous HD process to extract and analyze the known EM field. It provides much clearer insight into field coupling and radiation mechanism that is valuable to electromagnetic interference (EMI) and electromagnetic compatibility (EMC) analysis. Compared to the loop-tree based decomposition that is a quasi-HD, the proposed method is rigorous and frequency-independent. The algorithm verification and its application to coupling and resonating problems are presented. This method can provide a novel angle for the EM field analysis used in EMI/EMC, antennas, signal integrity, and relevant areas. © 2014 Wiley Periodicals, Inc. Microwave Opt Technol Lett 56:1838–1843, 2014

In this article, we describe a newly developed integral equation domain decomposition method for solving complex low frequency electromagnetic problems. This method is based on low frequency augmented equivalence principle algorithm (EPA) with the augmented electric field integral equation (A-EFIE). The A-EFIE provides a stable solution in the low-frequency regime as it includes both charge and current as unknowns to avoid the imbalance between the vector potential and the scalar potential. Based on similar idea, the augmented EPA can suppress the projection error resulting from low-frequency problems of the normal EPA. Combining these two methods, the proposed algorithm can be used in domain decomposition problems and is numerically stable at low frequencies. Several numerical examples are provided to verify its validity. © 2013 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:2475–2479, 2013

It is well known that electric field integral equation (EFIE) has the low frequency breakdown problem due to the decoupling of electric and magnetic field. Augmented electric field integral equation (AEFIE) method overcomes the low frequency breakdown. However, its performance degrades with the increasing frequency. To obtain a unified method that works for both low and high frequencies, a novel method using the EFIE complement process inside AEFIE is proposed. Numerical results demonstrated that this alternative AEFIE-EFIE method is able to extend integral equations to wide band applications. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:1737–1740, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26919

A new method, the low-frequency fast inhomogeneous plane-wave algorithm (LF-FIPWA) is presented to extend the traditional multilevel fast multipole algorithm (MLFMA) and fast inhomogeneous plane-wave algorithm (FIPWA) seamlessly into the low-frequency range. It uses evanescent-wave extrapolation and translation techniques to overcome the low-frequency breakdown problem. The accuracy can be well controlled over a broad frequency range. Numerical examples show the effectiveness of this new algorithm. © 2004 Wiley Periodicals, Inc. Microwave Opt Technol Lett 40: 117–122, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.11302

A new fast evanescent wave algorithm (FEWA) is introduced in the two-dimensional (2-D) case. It expands the Green's function into propagating waves and directional evanescent waves. Applying the evanescent wave correction technique, a procedure similar to the traditional MLFMA can be expedited. No buffer region is necessary anymore, and fewer translators are needed. Numerical examples are given to show the features of this method. © 2001 John Wiley & Sons, Inc. Microwave Opt Technol Lett 31: 460–465, 2001.

The method of hydriding combustion synthesis has been employed to prepare a ternary La 1.5 Mg 17 Ni 0.5 alloy that exhibits a large hydrogen storage capacity rapidly hydriding/dehydriding (H/D) kinetics at moderate conditions. The ternary La 1.5 Mg 17 Ni 0.5 alloy shows much better H/D kinetics than pure Mg, the binary Mg–Ni and Mg–La hydrogen storage alloys. It can absorb 5.40 mass% H at 573 K at excellent speed without any activation process. This composite absorbed 90% of its full hydrogen capacity (4.34 mass% H) and desorbed the same percentage (4.12 mass% H) in 2 Mg 17 under the same conditions. Moreover, it can absorb 4.10 mass% H and desorb 4.01 mass% H at low temperature (473 K), respectively. This attractive characteristic of the alloy can be explained by the catalytic action of LaNi 5 +LaH 3 +La as well as the multiphase structure which existed in the reaction process.