Application of Multiphase Dielectric Mixing Models for Understanding the Effective Dielectric Permittivity of Frozen Soils

2013 ◽  
Vol 12 (1) ◽  
pp. vzj2012.0060 ◽  
Author(s):  
Hailong He ◽  
Miles Dyck
Keyword(s):  
Dielectric Permittivity ◽  
Mixing Models ◽  
Frozen Soils ◽  
Effective Dielectric Permittivity

Optical bistability of planar metal/dielectric nonlinear nanostructures

2006 ◽  
Vol 14 (3) ◽  
Author(s):  
R. Noskov ◽  
A. Zharov
Keyword(s):  
Dielectric Permittivity ◽  
Field Intensity ◽  
Optical Bistability ◽  
Nonlinear Response ◽  
Nanoscale Devices ◽  
Nonlinear Dielectric ◽  
Transmission Properties ◽  
All Optical ◽  
Effective Dielectric Permittivity

AbstractWe study theoretically a nonlinear response of the planar metal/dielectric nanostructures constituted from periodical array of ultra thin silver layers and the layers of Kerr-like nonlinear dielectric. We predict hysteresis-type dependences of the components of the tensor of effective dielectric permittivity on the field intensity allowing the change in material transmission properties from transparent to opaque and back at extremely low intensities of the light. It makes possible to control the light by light in all-optical nanoscale devices and circuits.

scholarly journals Energy tunneling through narrow waveguide channel and design of small antennas

2011 ◽  
Vol 8 (1) ◽  
pp. 63-71
Author(s):  
Miranda Mitrovic ◽  
Branka Jokanovic
Keyword(s):  
Wave Propagation ◽  
Dielectric Permittivity ◽  
Transmission Coefficient ◽  
Rectangular Waveguide ◽  
Narrow Channel ◽  
Waveguide Channel ◽  
Small Antennas ◽  
Field Density ◽  
Effective Dielectric Permittivity ◽  
Small Antenna

In this paper we investigate the conditions for energy tunneling through narrow channel obtained by reducing the height of rectangular waveguide. Tunneling of the energy occurs at the frequency for which the effective dielectric permittivity of the channel becomes equal to zero, so it can be treated as an ENZ (epsilon-near-zero) metamaterial. We investigated how geometry of the channel and dielectric permittivity affect the transmission coefficient and field density in the channel. Adding slots in the channel, which are placed orthogonally to the wave propagation, we designed a small antenna with directivity of 5.44 dBi at the frequency of 3 GHz.

Complex Effective Dielectric Permittivity and Characteristic Impedance of Tunable Coplanar Line

2020 ◽  
Vol 63 (6) ◽  
pp. 281-288
Author(s):  
Artem S. Chernov ◽  
Irina P. Golubeva ◽  
Victor A. Kazmirenko ◽  
Yuriy V. Prokopenko
Keyword(s):  
Dielectric Permittivity ◽  
Characteristic Impedance ◽  
Coplanar Line ◽  
Effective Dielectric Permittivity

scholarly journals Free charge localization and effective dielectric permittivity in oxides

2016 ◽  
Vol 06 (02) ◽  
pp. 1630006 ◽  
Author(s):  
Mario Maglione
Keyword(s):  
Dielectric Permittivity ◽  
Ferroelectric Materials ◽  
Free Charge ◽  
Dielectric Spectra ◽  
Charge Localization ◽  
Giant Dielectric ◽  
Effective Dielectric Permittivity ◽  
Electronic Configurations ◽  
High Dielectric ◽  
Residual Impurities

This review will deal with several types of free charge localization in oxides and their consequences on the effective dielectric spectra of such materials. The first one is the polaronic localization at the unit cell scale on residual impurities in ferroelectric networks. The second one is the collective localization of free charge at macroscopic interfaces like surfaces, electrodes and grain boundaries in ceramics. Polarons have been observed in many oxide perovskites mostly when cations having several stable electronic configurations are present. In manganites, the density of such polarons is so high as to drive a net lattice of interacting polarons. On the other hand, in ferroelectric materials like BaTiO3 and LiNbO3, the density of polarons is usually very small but they can influence strongly the macroscopic conductivity. The contribution of such polarons to the dielectric spectra of ferroelectric materials is described. Even residual impurities as for example Iron can induce well-defined anomalies at very low temperatures. This is mostly resulting from the interaction between localized polarons and the highly polarizable ferroelectric network in which they are embedded. The case of such residual polarons in SrTiO3 will be described in more detail, emphasizing the quantum polaron state at liquid helium temperatures. Recently, several nonferroelectric oxides have been shown to display giant effective dielectric permittivity. It is first shown that the frequency/temperature behavior of such parameters is very similar in very different compounds (donor-doped BaTiO3, CaCu3Ti4O12, LuFe2O4, Li-doped NiO, etc.). This similarity calls for a common origin of the giant dielectric permittivity in these compounds. A space charge localization at macroscopic interfaces can be the key for such extremely high dielectric permittivity.

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