Plane-Wave Propagation in Electromagnetic PQ Medium

TL;DR

This paper introduces the general class of PQ electromagnetic media, derives the quartic dispersion equation for plane waves using dyadic formalism, and analyzes specific cases and a numerical example of the dispersion surface.

Contribution

It generalizes P and Q media into PQ media and derives the analytic quartic dispersion equation for plane wave propagation.

Findings

Dispersion equation reduces to quadratic forms in special cases

Verification through known special cases

Numerical example of a non-decomposable dispersion surface

Abstract

Two basic classes of electromagnetic media, recently defined and labeled as those of P media and Q media, are generalized to define the class of PQ media. Plane wave propagation in the general PQ medium is studied and the quartic dispersion equation is derived in analytic form applying four-dimensional dyadic formalism. The result is verified by considering various special cases of PQ media for which the dispersion equation is known to decompose to two quadratic equations or be identically satisfied (media with no dispersion equation). As a numerical example, the dispersion surface of a PQ medium with non-decomposable dispersion equation is considered.