College Physics

The experimental research of electronic diffraction by G.P.Thomson

LU Wen-tao

Published Jan 1, 2004• 0 citations

Abstract

Sir George Paget Thomson completed the experiment of electron diffraction with method different from Davisson,and proved the correctness of the ideas referred matter waves by de Broglie.From his research experiences,we can see the importance of selecting correct subject of research,guiding role of the theory and the effect of his scientific research methods.

Related papers

Electron diffraction chez Thomson: early responses to quantum physics in Britain

Jaume Navarro

Abstract In 1927, George Paget Thomson, professor at the University of Aberdeen, obtained photographs that he interpreted as evidence for electron diffraction. These photographs were in total agreement with de Broglie's principle of wave–particle duality, a basic tenet of the new quantum wave mechanics. His experiments were an initially unforeseen spin-off from a project he had started in Cambridge with his father, Joseph John Thomson, on the study of positive rays. This paper addresses the scientific relationship between the Thomsons, father and son, as well as the influence that the institutional milieu of Cambridge had on the early work of the latter. Both Thomsons were trained in the pedagogical tradition of classical physics in the Cambridge Mathematical Tripos, and this certainly influenced their understanding of quantum physics and early quantum mechanics. In this paper, I analyse the responses of both father and son to the photographs of electron diffraction: a confirmation of the existence of the ether in the former, and a partial embrace of some ideas of the new quantum mechanics in the latter.

The British Journal for the History of ScienceFeb 5, 20109 citations

Davisson-Germer Experiment

Promita Ghosh

This article is about the experiment which provided the first evidence of matter waves. In 1927 Davidson and Germer provided the first experimental evidence of matter waves through diffraction of slow electrons, the associated de Broglie wavelength of which is of the order of atomic spacings of most of the crystalline solids. Thus the atoms of a crystal can serve as a three dimensional array of diffracting centers for the de Broglie matter waves.

Jun 23, 20210 citations

Double-slit interference and single-slit diffraction experiments on electrons

Huawang Li

De Broglie proposed the matter wave in 1924. The de Broglie wave is neither a mechanical wave nor an electromagnetic wave and has a very short wavelength. The Davisson-Germer electron diffraction experiment performed in 1925 involved bombarding the surface of a nickel crystal with a narrow beam of electrons. When the accelerating voltage V was maintained at 54 V, the wavelength of the incident electron was λ=h/ 2 m e V = 0.167 nm [Y. S. Chen and Z. Z. Li, College Physics (Tianjin University, Tianjin, 1999)] demonstrating the existence of the matter wave. We introduce a type of electron wave with a very long wavelength in this study that is different from the matter wave. For example, the wavelength of the electron wave can reach 0.43 mm in the double-slit interference of electrons. Experiments demonstrate that this long-wavelength electron wave can produce both double-slit interference and electron diffraction. A comparative analysis of matter and electron waves reveals the physical natures of these waves and wave‐particle duality.

Physics EssaysSep 3, 20220 citations

Measuring the de Broglie wavelength of electrons using Thomson e/m tube

Swarnava Mitra

The Thomson e/m experiment laid the foundation of the first atomic particle and for once proved the existence of discrete charged particles, now known as electrons. This work aims at studying the wave nature of electrons by measuring their de Broglie wavelengths. The wavelength was obtained from two different facets, namely, the electric field and the magnetic field, and then it has been shown that the two values are in agreement with each other to an order of 10−11 m.

Nov 20, 20210 citations

Uncertainties relation and micro particles diffraction

A.P. Pylaev

It was shown that for explanation of experimental results on diffraction of micro particles it does no need to use the de Broglie wave’s concept. Such the results can be described with the aid of the Heisenberg uncertainties relation. As for examples the known results of experiments conducted by C. Davisson and L. H. Germer on diffraction of electrons and by Rutherford on  particles scattering are considered.

ТЕНДЕНЦИИ РАЗВИТИЯ НАУКИ И ОБРАЗОВАНИЯApr 1, 20210 citations

Re-understanding of Wave-particle Duality

Chun Wang

The author has worked with high-resolution transmission electron microscope for many years, which provides the most direct evidence of wave-particle duality. This relates to Crookes and J. J. Thomson's cathode rays tubes to determine that electron beams are of particle nature. This also relates to Röntgen's discovery that when an electron beam in the cathode rays tube strikes the glass wall, it produces X-rays with extremely high penetrating power. This behavior is consistent with Maxwell-Lorentz’s electrodynamics that electromagnetic waves must be produced whenever electricity carriers alter their velocity. The wave-particle duality proposed by de Broglie refers to accelerated electron beam, rather than single electron. De Broglie emphasized that the crystallographic diffraction pattern produced by his electron beam was completely consistent with the crystallographic diffraction pattern of von Laue by X-rays, therefore, he proposed that electrons possess wave-particle duality. This is actually the selected area electron diffraction pattern in transmission microscope. It is X-rays, not the waves of the electrons themselves to produce diffraction pattern. He extended this to the wave-particle duality of all matter and light. Schrödinger directly introduced de Broglie's electron beam behavior into electron wave in atoms. It was just at this stage that illogical reasoning occurred, making the quantum theory increasingly difficult to understand.

Engineering Open AccessJan 6, 20260 citations