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Dielectric relaxation in solids

TL;DR: In this paper, a broad-brush view of dielectric relaxation in solids is presented, making use of the existence of a universality of Dielectric response regardless of a wide diversity of materials and structures with dipolar as well as charge-carrier polarization.
Abstract: This review presents a wide-ranging broad-brush picture of dielectric relaxation in solids, making use of the existence of a `universality' of dielectric response regardless of a wide diversity of materials and structures, with dipolar as well as charge-carrier polarization. The review of the experimental evidence includes extreme examples of highly conducting materials showing strongly dispersive behaviour, low-loss materials with a `flat', frequency-independent susceptibility, dipolar loss peaks etc. The surprising conclusion is that despite the evident complexity of the relaxation processes certain very simple relations prevail and this leads to a better insight into the nature of these processes.
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TL;DR: In this article, a comprehensive survey is given of the experimental a.c. data for two types of amorphous semiconductor, namely chalcogenide and pnictide materials, and it is concluded that the behavior at intermediate to high temperatures is well accounted for by the correlated-barrier-hopping model, whereas the low-temperature behaviour is probably due to atomic tunnelling.
Abstract: The various origins of a frequency-dependent conductivity in amorphous semiconductors are reviewed, stressing particularly recent advances and the influences that factors such as correlation and non-random spatial distributions of electrically active centres can have on the a.c. conductivity. A comprehensive survey is given of the experimental a.c. data for two types of amorphous semiconductor, namely chalcogenide and pnictide materials. It is concluded that the a.c. behaviour at intermediate to high temperatures is well accounted for by the correlated-barrier-hopping model, whereas the low-temperature behaviour is probably due to atomic tunnelling.

1,814 citations

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1,205 citations

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TL;DR: In this paper, the incorporation of silica nanoparticles into polyethylene increased the breakdown strength and voltage endurance significantly compared to the inclusion of micron scale fillers, and showed a decrease in dielectric permittivity for the nanocomposite over the base polymer.
Abstract: The incorporation of silica nanoparticles into polyethylene increased the breakdown strength and voltage endurance significantly compared to the incorporation of micron scale fillers. In addition, dielectric spectroscopy showed a decrease in dielectric permittivity for the nanocomposite over the base polymer, and changes in the space charge distribution and dynamics have been documented. The most significant difference between micron scale and nanoscale fillers is the tremendous increase in interfacial area in nanocomposites. Because the interfacial region (interaction zone) is likely to be pivotal in controlling properties, the bonding between the silica and polyethylene was characterized using Fourier transformed infrared (FTTR) spectroscopy, electron paramagnetic resonance (EPR), and x-ray photoelectron spectroscopy (XPS). The picture which is emerging suggests that the enhanced interfacial zone, in addition to particle-polymer bonding, plays a very important role in determining the dielectric behavior of nanocomposites.

817 citations


Cites methods from "Dielectric relaxation in solids"

  • ...The activation energy (shown in Figure 10b was calculated by the normalization method [34] by shifting the frequency spectra laterally and then determining the frequency shift required to bring the curves into coincidence....

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TL;DR: The following topics are discussed: a summary of dielectric theory; amino acids, peptides, proteins and DNA; bound water in biological systems; biological electrolytes; membranes and cells; tissues.
Abstract: The following topics are discussed: a summary of dielectric theory; amino acids, peptides, proteins and DNA; bound water in biological systems; biological electrolytes; membranes and cells; tissues.

699 citations

Journal ArticleDOI
TL;DR: In this article, it is shown that in a medium representing an example of "Koch's tree" type fractional structure the diffusion process is described by a generalized transfer equation in partial derivations.
Abstract: It is shown that in a medium representing an example of “Koch's tree”-type fractional structure the diffusion process is described by a generalized transfer equation in partial derivations. Such a structure can serve as a model of a porous medium where the diffusion process takes place. The geometry of an inhomogeneous medium can serve as the dicisive factor in the explanation of the “universal response” phenomenon. A range of frequencies is found where such “superslow” diffusion process can be observed. [Russian Text Ignored].

660 citations

References
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Journal ArticleDOI
01 Jun 1977-Nature
TL;DR: A review of dielectric data for a wide range of solids proves the existence of a remarkable "universality" of frequency and time responses which is essentially incompatible with the multiplicity of currently accepted detailed interpretations as discussed by the authors.
Abstract: A review of dielectric data for a wide range of solids proves the existence of a remarkable ‘universality’ of frequency and time responses which is essentially incompatible with the multiplicity of currently accepted detailed interpretations. Certain unique features of the universal behaviour strongly suggest the dominant role of many-body interactions.

4,234 citations

Book
01 Jan 1979
TL;DR: In this article, a brief description is given of the various manifestations of the universal fractional power law relaxation processes, which are contrasted with the classical or Debye law, and a novel very general approach based on the so-called energy criterion is introduced.
Abstract: A brief description is given of the various manifestations of the universal fractional power law relaxation processes, which are contrasted with the classical or Debye law. It is shown that the universal law is indeed found in a remarkable variety of physical and chemical situations, and this is deemed to merit a special attempt at finding a suitably general theoretical model. Several such models are briefly described, and a novel very general approach based on the so-called energy criterion is introduced. It is concluded that it is not yet possible to establish with certainty the validity of any of the models. >

4,012 citations

Journal ArticleDOI
TL;DR: In this paper, a simple theory based on the currently accepted model of impurity conduction is given for the higher temperature range, which accounts well for the observed frequency and concentration dependences, but only order-of-magnitude absolute agreement is obtained.
Abstract: The complex conductivity has been measured in $n$-type silicon with various kinds of impurities at frequencies between ${10}^{2}$ and ${10}^{5}$ cps and temperatures between 1 and 20\ifmmode^\circ\else\textdegree\fi{}K. In most cases it is orders of magnitude larger than the measured dc conductivity and is attributed to polarization caused by hopping processes. The observed frequency dependence in the measured range can be expressed as $A{\ensuremath{\omega}}^{0.8}$, where $A$ is a complex constant. At the low-temperature end the conductivity is roughly proportional to minority impurity concentration and is almost independent of the majority impurity concentration and At higher temperatures the conductivity becomes approximately proportional to the product of both concentrations. A simple theory, based on the currently accepted model of impurity conduction, is given for the higher temperature range. It accounts well for the observed frequency and concentration dependences. However, only order-of-magnitude absolute agreement is obtained.

1,023 citations

Journal ArticleDOI
TL;DR: In this article, a new theory is proposed for the explanation of observed relaxation phenomena, which differs significantly from theories suggested by the authors before, and is based on a model of structural organization of macroscopically sized samples of imperfectly structured materials, both solids and liquids.
Abstract: A new theory is proposed for the explanation of observed relaxation phenomena, which differs significantly from theories suggested by the authors before. The theory is based on a model of structural organization of macroscopically sized samples of imperfectly structured materials, both solids and liquids, and is intermediate in character. In terms of the model, a microscopic structure is maintained over a cluster containing a number of microscopic units, with an array of clusters described by a steady-state distribution completing the macroscopic picture. The structural regularity of each level of morphological organization is precisely defined by a coarse-grained index, which is given a thermodynamic interpretation in terms of binding energies and configurational entropy. The limiting cases of an ideal liquid and a perfect crystal are recovered as asymptotic extremes in terms of this definition. The consequences of this model for the relaxation dynamics of the structure are examined and it is shown that prepared fluctuations decay in a time-power law manner as coupled zero-point motions evolve either within clusters or between clusters, with a power determined by the relevant regularity index. As a result, the origin of power law noise in materials is explained in terms of configurational entropy, and its relation with gaussian and white noise, which appear as asymptotic limits, outlined. The shape of the steady-state distribution of the array of clusters is also determined without any a priori assumptions, and it is shown to range from an unbounded form to a δ function as the regularity of the array superstructure increases. Experimental examples of dielectric relaxation spectroscopy have been used to illustrate these structural concepts and outline the way in which this technique can be used to deduce the structural organization of the sample. Finally, a short description is given of some commonly observed forms of response and their structural interpretation.

271 citations