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In our previous work [B. Guo and M. Q. Xie, Optik 125 , 2137 (2014)], we found that plasma photonic crystal (PC), which proposed is a multilayer stack of alternating plasma layer and dielectric, can show negative refraction not only at the frequency edge of the band gap but also at some other frequencies which do not belong to any band gaps when the frequency of oblique incidence is below the plasma frequency by analyzing the dispersion relations. Here, in this paper, we investigate further the negative refraction in plasma PCs at below plasma frequency by studying the group and phase indices. The negative group and positive phase indices of refraction are observed at below plasma frequency for oblique incidence, which denotes the occurrence of negative refraction. Moreover, the results show that the proposed plasma PCs exhibit negative refraction in two frequency regions which is same to our previous work and the frequency regions of negative refraction can be tunable. Parameter dependence of the effects is examined and discussed. [ABSTRACT FROM AUTHOR]

The dispersion relations for electromagnetic wave propagation in chiral plasmas are derived using a simplified method and investigated in detail. With the help of the dispersion relations for each eignwave, we explore how the chiral plasmas exhibit negative refraction and investigate the frequency region for negative refraction. The results show that chirality can induce negative refraction in plasmas. Moreover, both the degree of chirality and the external magnetic field have a significant effect on the critical frequency and the bandwidth of the frequency for negative refraction in chiral plasmas. The parameter dependence of the effects is calculated and discussed. [ABSTRACT FROM AUTHOR]

Abstract: We have theoretically explored the negative refraction (NR) in one-dimensional plasma photonic crystals (PCs) consisting of plasma and dielectric materials. By using the transfer matrix method and Bloch theorem, we have studied the group velocity and we have obtained the NR in plasma PCs with the help of the group velocity. The results show that plasma PCs can also exhibit the NR although they have a periodically modulated positive permittivity ɛ and permeability μ. It is also shown that the NR in plasma PCs exhibits difference behaviour in different frequency regions, ω < ω p and ω > ω p , respectively. The parameter dependence of the effects is also examined and discussed. [Copyright &y& Elsevier]

A plasma metamaterial that exhibits negative refraction in the terahertz region of the spectrum has been demonstrated in the present communication. The plasma metamaterial is an uniaxial anisotropic metamaterial which is a multilayer stack of alternating plasma layer and background material. The negative refraction in the terahertz region of the proposed metamaterial is explored. The effects of the losses in plasma, plasma density, plasma filling factor, and dielectric constant of background material on the critical frequency ω0 and the band width of negative refraction Δω are examined and discussed. [ABSTRACT FROM AUTHOR]

The behaviors of negative refraction of electromagnetic waves propagation at the dielectric–magnetized plasma interface are investigated in detail. The Faraday and Voigt effects on the properties of negative refraction are calculated and discussed. The results show that the behavior of negative refraction can be tuned and controlled correspondingly due to the magneto-optical effects. The properties of negative refraction behave differently in different frequency region and the magnitude of external magnetic field. Moreover, negative refraction can be realized at the dielectric–magnetized plasma interface above the plasma frequency, which is different from the case of dielectric–plasma interface. [ABSTRACT FROM AUTHOR]

Characteristic equations in magnetized plasma with chirality are derived in simple formulations and the dispersion relations for propagation parallel and perpendicular to the external magnetic field are studied in detail. With the help of the dispersion relations of each eigenwave, the author explores chirality-induced negative refraction in magnetized plasma and investigates the effects of parameters (i.e., chirality degree, external magnetic field, etc.) on the negative refraction. The results show that the chirality is the necessary and only one factor which leads to negative refraction without manipulating electrical permittivity and magnetic permeability. Both increasing the degree of chirality and reducing the external magnetic field can result in greater range negative refraction. Parameter dependence of the effects is calculated and discussed. [ABSTRACT FROM AUTHOR]

Negative refraction in one- and two-dimensional lossless plasma dielectric photonic crystals consisting of plasma and background materials is theoretically investigated and the necessary conditions for negative refraction in these two structures are obtained. The critical frequency ω0 and the bandwidth Δω for negative refraction are explored, and the parameter dependence of effects such as plasma filling factor and the dielectric constant of background materials is also examined and discussed. [ABSTRACT FROM AUTHOR]