Module 5 : MODERN PHYSICS
Lecture 26 : Wave Nature of Particle - the de Broglie Hypothesis
Electron Diffraction from a Crystal
  Consider a beam of electron with a speed $ 5\times 10^6$ m/s corresponding to a wavelength $ \lambda = h/mv = 0.14$ nm. Such a wave may be diffracted by gratings with separation of similar order as that of the wavelength. Crystals provide such natural gratings.
  Davisson - Germer Experiment :
Experimental confirmation of de Broglie hypothesis was provided in 1926 by Davisson and Germer, who studied diffraction of a beam of electrons from the surface of a nickel crystal.
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