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Hence we identify = =, means that allowed scattering vectors = are those equal to reciprocal lattice vectors for a crystal in diffraction, and this is the meaning of the Laue equations. This fact is sometimes called the Laue condition .
In quantum physics, diffraction in time is a phenomenon associated with the quantum dynamics of suddenly released matter waves initially confined in a region of space. It was introduced in 1952 by Ukrainian-Mexican physicist Marcos Moshinsky with the shutter problem . [ 1 ]
Diffraction is the same physical effect as interference, but interference is typically applied to superposition of a few waves and the term diffraction is used when many waves are superposed. [1]: 433 Italian scientist Francesco Maria Grimaldi coined the word diffraction and was the first to record accurate observations of the phenomenon in 1660.
The dynamical theory of diffraction describes the interaction of waves with a regular lattice. The wave fields traditionally described are X-rays , neutrons or electrons and the regular lattice are atomic crystal structures or nanometer -scale multi-layers or self-arranged systems.
Beyond the equations of motion, other aspects of matter wave optics differ from the corresponding light optics cases. Sensitivity of matter waves to environmental condition. Many examples of electromagnetic (light) diffraction occur in air under many environmental conditions.
The concept of Bragg diffraction applies equally to neutron diffraction [4] and approximately to electron diffraction. [5] In both cases the wavelengths are comparable with inter-atomic distances (~ 150 pm). Many other types of matter waves have also been shown to diffract, [6] [7] and also light from objects with a larger ordered structure ...
More generally, "waveguide" dispersion can occur for waves propagating through any inhomogeneous structure (e.g., a photonic crystal), whether or not the waves are confined to some region. [dubious – discuss] In a waveguide, both types of dispersion will generally be present, although they are not strictly additive.
To understand the process, it is helpful to understand interference and diffraction. Interference occurs when one or more wavefronts are superimposed. Diffraction occurs when a wavefront encounters an object. The process of producing a holographic reconstruction is explained below purely in terms of interference and diffraction.