Magnetic polarization field, charged particles

The electric and magnetic polarization fields P(x), M(x) are invoked to describe the electrodynamic properties of charged particles they enter the theory through a representation of the lagrangian interaction potential for a closed system of electric charges and the electromagnetic field... 

It seems natural to assume that polar crystals would be a source of electric fields around them just as magnets are a source of magnetic fields. In practice, however, the net dipole moment is not detectable in ferroelectrics because the surface charges are usually rapidly neutralized by ambient charged particles. 

Figure 18.2 The aurora borealis, or northern lights. This luminous display in the northern sky is produced by collisions of high-speed electrons and protons from the Sun with air molecules. The charged particles are channeled toward the polar regions by Earth s magnetic field. 

Fig. 11.4 Schemes demonstrating two SERS mechanisms, (a) Local field concentration near the gap between two particles [19]. The white spheres and polygons are silver, and the color scale bar indicates the electro-magnetic field enhancement. The separation distance is 1 and 5.5 nm for the first and second columns, respectively. The wavelength of the incident field is 514.5 nm with vertical polarization, and (b) Possible charge transfer excitations between molecule and metal [22]. The occupied and unoccupied molecular orbitals are broadened by the molecule-metal interactions. Metal-to-molecule and molecule-to-metal charge transfers are indicated by arrows...

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