Waves and negative refraction in magnetized plasma with ferrite grains

Abstract

The propagation of high frequency electromagnetic waves in the low temperature magnetized plasma with ferrite grains (MPFG) is considered. The dispersion properties of MPFG are simultaneously characterized by the permittivity and permeability tensors. The dispersion of the permeability is caused by the high frequency magnetization of the grain subsystem and is important in the vicinity of the frequency of ferromagnetic resonance, which coincides with the electron cyclotron frequency ωc. The MPFG becomes transparent for the waves that cannot propagate in conventional electron-ion magnetized plasma. It is shown that the refractive index of the extraordinary wave propagating along and transversal to the external magnetic field with frequencies close to ωc can be negative as well as positive. For the typical parameters of MPFG, the group velocity of this wave is much smaller than the speed of light. The refractive index of MPFG matched with the free space is obtained for waves propagating at an arbitrary angle with respect to the applied constant magnetic field. The results obtained clearly shows that the dispersion properties of MPFG have all the known properties of left-handed media in the vicinity of ωc.

Dispersion peculiarities of hybrid modes in a circular waveguide filled by a composite gyroelectromagnetic medium

“…In order to realize such a gyroelectromagnetic filling of actual microwave waveguide systems, it is proposed to use a low temperature magnetized plasma admixed by micron ferrite grains (e.g. yttrium iron garnet) [35]. In this mixture the material dispersion of permeability is caused by the high frequency magnetization of the grain subsystem which is important in the vicinity of a ferromagnetic resonance.…”

Polaritons dispersion in a composite ferrite-semiconductor structure near gyrotropic-nihility state

“…Since further our goal is to elucidate the dispersion laws of the bulk polaritons (which are in fact eigenwaves), we are interested in real solutions of the first equation in (14) for the TE mode. In order to find the real solutions related to eigenwaves, absence of losses in constitutive parameters of the underlying layers is supposed, i.e.…”

“…As relevant examples layered magnetic-semiconductor heterostructures [10,11,12,13] and the magnetized electron-ion plasma consisting micron ferrite grains [14] can be mentioned. Such gyroelectromagnetic composites are now usually considered within the theory of metamaterials, in the framework of which they are widely discussed from the viewpoint of achieving negative refraction and backward wave propagation 2 .…”

Gyrotropic-nihility state in a composite ferrite-semiconductor structure

“…Its constituents are micron ferrite grains (e.g. yttrium iron garnet, YIG) admixed to the magnetized electron-ion plasma [20]. The dispersion of permeability is caused by the high frequency magnetization of the grain subsystem and is important in the vicinity of the frequency of a ferromagnetic resonance, which coincides with the electron cyclotron frequency.…”

“…Evidently, the formulation of the eigenvalue problem on the matrix A ef f (det[A ef f − ηI] = 0), whose coefficients are defined as (11), yields us the characteristic equation on the effective refractive index η of the medium. Thus, we arrive to the following biquadratic equation with respect to η 2 [18,20]:…”