Backscattering of electrons from grain boundaries refers to the phenomenon in which an incident electron beam is scattered back towards the source by the atomic lattice of a material at a grain boundary. The scattering occurs when the electron beam interacts with the atomic structure of the material, and some of the electrons are scattered in a direction opposite to the original beam direction.

Grain boundaries are the interfaces between grains (i.e., crystalline regions) in a polycrystalline material. These boundaries have different atomic arrangements than the grains themselves, and therefore, electrons passing through the grain boundary experience a change in the local potential energy landscape. This leads to a scattering of electrons back towards the source.

The probability of backscattering depends on the energy of the incident electrons, the angle of incidence, and the nature of the material. Higher incident energies, larger angles of incidence, and materials with larger atomic number or higher density tend to have a higher backscattering probability.

The backscattering process is commonly used in materials science for various applications, such as characterizing grain boundaries, measuring crystallographic orientations, and probing surface structures. It is also used in electron microscopy techniques, such as backscattered electron imaging and electron backscatter diffraction, to obtain information about the microstructure and texture of materials.

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Febin Cherian John Can dipoles be backscattered by grain boundaries and align or polarize in the opposite direction of the electric field at higher frequency and temperature?