$what is electron diffraction$

A new theory shows that when electrons strongly interact with phonons, they will form a united electron-phonon liquid. 'Typically, electrons are scattered by phonons which leads to the usual diffusive motion of electrons in metals. 'We wanted to test a recent prediction of the 'electron-phonon fluid,'' Tafti said, noting that phonons are the vibrations of a crystal structure. From the slope of the graph the interatomic spacings of carbon can be calculated.Īlso available is the same system but with the MCP power supply.The findings mark the first discovery of an electron-phonon liquid inside NbGe2, Tafti said. Combining the two equations one can show that the diameter of the rings is proportional to (V)^(-1/2).Ī graph like the one in figure 3 is obtained by plotting (V)^(-1/2) vs. Additionally, from the geometry of the tube (figure 2), we see that θ=D/2L where θ≈sin⁡θ for small angles, D is the diameter of the ring and L is the length from the graphite target to the luminescent screen. One can show that the wavelength of an electron λ=d sin⁡θ. As the electron beam penetrates this carbon target, the electrons are diffracted into two rings corresponding to separations of the carbon atoms. A micro mesh nickel grid, onto which graphite has been deposited, lies across the exit aperture of the electron “gun” (figure 1). The inside surface of the end of the tube has a luminescent screen deposited on it. The Electron Diffraction Tube emits from an indirectly heated, oxide coated cathode, a narrow converging beam of electrons. In addition, one can calculate the interatomic spacings of carbon, (the diffracting material in the tube). With the Electron Diffraction Tube one can verify the de Broglie hypothesis and establish the dual nature of the electron. Thomson's son provided experimental confirmation that electrons do act as waves. Three years later Davisson and Germer and later that same year J. In 1922 de Broglie combined Planck's quantum energy idea with an analysis of the Theory of Relativity and proposed that since waves sometimes act as particles perhaps particles sometimes act as waves with a wavelength of h/mv.

$what is electron diffraction$

What is electron diffraction