Frequency dependence of the constitutive parameters of causal perfectly matched anisotropic absorbers

Perfectly matched layers (PML's), which are employed for mesh truncation in the finite-difference time-domain (FDTD) or in finite element methods (FEM's), can be realized by artificial anisotropic materials with properly chosen permittivity and permeability tensors. The tensor constitutive parameters must satisfy the Kramers-Kronig relationships, so that the law of causality holds. These relations are used to relate the real and imaginary parts of the constitutive parameters of the PML media to deduce the asymptotic behaviors of these parameters at low and high frequencies.


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In the numerical solution of electromagnetic scattering and/or radiation problems by finite methods, a mesh truncation scheme must be employed in order to obtain a bounded computational domain. We discuss the realization of perfectly matched absorbers by means of a complex coordinate transformation in a general coordinate system. In this way, it is possible to design perfectly matched layers (PMLs) which are conformal to the antenna/scatterer surface. The performance of the PMLs are tested for certain probl...
Citation Formats
M. Kuzuoğlu, “Frequency dependence of the constitutive parameters of causal perfectly matched anisotropic absorbers,” IEEE MICROWAVE AND GUIDED WAVE LETTERS, pp. 447–449, 1996, Accessed: 00, 2020. [Online]. Available: