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Maxwell equation, dielectric relaxation

In the nineteenth century, the Maxwell equations appeared, based upon electromagnetic theory and juxtaposed with light. In the twentieth century came the Debye tradition of regarding biomolecules as polar materials with exponential relaxation. However, experimental findings showed that most dielectrics do not show exponential relaxation, but fractional power law relaxation. Fractional power law was the universal property. Then came the Cole models based upon a new component, the constant phase element (CPE). [Pg.38]

The paradox with such a reasoning is that the dielectric relaxation-like model invoked relies on the influence of time (and on the existence of conduction), which modifies the wave pulsation and contradicts the form of Maxwell equations used (no current involved). [Pg.560]

Keywords dielectric relaxation, dielectric strength permittivity, dipole moment, polarization, relaxation, conductivity, relaxation time distribution, activation energy, Arrhenius equation, WLF-equation, Maxwell-Wagner polarization. [Pg.171]

Conduction band electrons in metals are able to interact with an optical electric field Their motion is damped by collisions with the vibrating lattice and so some of the light energy is transferred to the lattice. In this manner the material is heated. In semiconductors the motions of both electrons in the conduction band and holes in the valence band must be considered. In dielectrics the electrons are effectively bound to the atoms or molecules that compose the material. The appUed optical field induces a polarization in the material. Upon relaxation some of the energy in the polarization is coupled to the lattice and the material is heated. These processes of absorption of energy from an optical field can be treated by classical electromagnetics. That is. Maxwell s equations, the constitutive equations of matter, and the boundary conditions for each material can be solved in each case. [Pg.2]


See other pages where Maxwell equation, dielectric relaxation is mentioned: [Pg.229]    [Pg.235]    [Pg.391]    [Pg.407]    [Pg.13]    [Pg.251]   


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