Reflection of Slow Atoms
Although the principles of quantum mechanics apply to any particles, usually the term quantum reflection means reflection of atoms from a surface of condensed matter (liquid or solid). The full potential experienced by the incident atom does become repulsive at a very small distance from the surface (of order of size of atoms). This is when the atom becomes aware of the discrete character of material. This repulsion is responsible for the classical scattering one would expect for particles incident on a surface. Such scattering is diffuse rather than specular, and so this component of the reflection is easy to distinguish. Indeed to reduce this part of the physical process, a grazing angle of incidence is used; this enhances the quantum reflection. This requirement of small incident velocities for the particles means that the non-relativistic approximation to quantum mechanics is all that is required.
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Famous quotes containing the words reflection of, reflection, slow and/or atoms:
“It is conceivable at least that a late generation, such as we presumably are, has particular need of the sketch, in order not to be strangled to death by inherited conceptions which preclude new births.... The sketch has direction, but no ending; the sketch as reflection of a view of life that is no longer conclusive, or is not yet conclusive.”
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“The Cretans are always liars, evil beasts, slow bellies.”
—Bible: New Testament St. Paul, in Titus, 1:12.
Cited by Paul, this remark is attributed to Epimenides.
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