201 research outputs found
Vector Potential Electromagnetic Theory with Generalized Gauge for Inhomogeneous Anisotropic Media
Vector and scalar potential formulation is valid from quantum theory to
classical electromagnetics. The rapid development in quantum optics calls for
electromagnetic solutions that straddle quantum physics as well as classical
physics. The vector potential formulation is a good candidate to bridge these
two regimes. Hence, there is a need to generalize this formulation to
inhomogeneous media. A generalized gauge is suggested for solving
electromagnetic problems in inhomogenous media which can be extended to the
anistropic case. The advantages of the resulting equations are their absence of
low-frequency catastrophe. Hence, usual differential equation solvers can be
used to solve them over multi-scale and broad bandwidth. It is shown that the
interface boundary conditions from the resulting equations reduce to those of
classical Maxwell's equations. Also, classical Green's theorem can be extended
to such a formulation, resulting in similar extinction theorem, and surface
integral equation formulation for surface scatterers. The integral equations
also do not exhibit low-frequency catastrophe as well as frequency imbalance as
observed in the classical formulation using E-H fields. The matrix
representation of the integral equation for a PEC scatterer is given.Comment: 16 pages, 2 figur
Combined Field Integral Equation Based Theory of Characteristic Mode
Conventional electric field integral equation based theory is susceptible to
the spurious internal resonance problem when the characteristic modes of closed
perfectly conducting objects are computed iteratively. In this paper, we
present a combined field integral equation based theory to remove the
difficulty of internal resonances in characteristic mode analysis. The electric
and magnetic field integral operators are shown to share a common set of
non-trivial characteristic pairs (values and modes), leading to a generalized
eigenvalue problem which is immune to the internal resonance corruption.
Numerical results are presented to validate the proposed formulation. This work
may offer efficient solutions to characteristic mode analysis which involves
electrically large closed surfaces
Casimir Force for Arbitrary Objects Using the Argument Principle and Boundary Element Methods
Recent progress in the simulation of Casimir forces between various objects
has allowed traditional computational electromagnetic solvers to be used to
find Casimir forces in arbitrary three-dimensional objects. The underlying
theory to these approaches requires knowledge and manipulation of quantum field
theory and statistical physics. We present a calculation of the Casimir force
using the method of moments via the argument principle. This simplified
derivation allows greater freedom in the moment matrix where the argument
principle can be used to calculate Casimir forces for arbitrary geometries and
materials with the use of various computational electromagnetic techniques.Comment: 6 pages, 2 figure
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