One unconventional phenomenon attendant on electromagnetic wave propagation in isotropic media with negative permittivity and permeability is the so-called ‘negative refraction’ implying that in this medium the refracted ray is located on the same side of the normal to the interface as the incident ray does. At the same time, the propagation vector of the transmitted wave is directed toward the boundary. The isotropic media with , escape detection in nature. Experimentally, these media are simulated by man-made composite materials in the form of volume periodic structures. In this connection, several authors have cast doubt on the fact that this effect is inherent in a continuous isotropic medium with negative permittivity rather than is caused by the periodicity of the material.
In the present paper, a model of inhomogeneous isotropic flat-layered lossless medium including spatial domains with conventional and double-negative media and with smooth monotonic transition between them is suggested. The electromagnetic wave transmitting through this medium has been described analytically. It has been shown, as a direct consequence of Maxwell’s equations and the energy conservation law, that of two admissible solutions of these equations, one of which describes a negative refraction, whereas the other is for a conventional one, only the former is physically feasible. The model presented has allowed us to describe exactly for the first time an electromagnetic field distribution in the vicinity of the point where and vanish.