Atomic Model and Wave-Particle Duality

How can we prove matter wave is real?The most direct way, as demonstrated by Laue for X-Ray, is by diffraction.According to the de Broglie relation, if one useselectrons, to have wavelength comparable to theatomic separation in crystals, the electrons cannothave energy more than 150 eV.Several groups in Europe tried but failed to see thediffraction from electrons.At Bell Labs, Clinton Davisson and Lester Germerwere studying the properties of the cathodes forvacuum tubes …which led to their discovery of theelectron diffraction.68