voltage of 54V at a scattering angle = 50º The appearance of the peak in a particular direction is due to the constructive interference of electrons scattered from different layers of the regularly spaced atoms of the crystals. From the electron diffraction measurements, the wavelength of matter waves was found to be . nm. The de Broglie wavelength # associated with electrons, using Eq.
( . ), for V = V is given by # = h / p V . nm # . nm = .
nm Thus, there is an excellent agreement between the theoretical value and the experimentally obtained value of de Broglie wavelength. Davisson- Germer experiment thus strikingly confirms the wave nature of electrons and the de Broglie relation. More recently, in , the wave nature of a beam of electrons was experimentally demonstrated in a double-slit experiment, similar to that used for the wave nature of light. Also, in an experiment in , interference fringes were obtained with the beams of iodine molecules, which are about a million times more massive than electrons.
The de Broglie hypothesis has been basic to the development of modern quantum mechanics. It has also led to the field of electron optics. The wave properties of electrons have been utilised in the design of electron microscope which is a great improvement, with higher resolution, over the optical microscope. Development of electron microscope