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Invention of the Point Contact Transistor, 1954


The electrons in an atom travel around the nucleus on specific bands, or tracks. Each track can hold one specific number of electrons, and once that track is full, any electrons that are left over must proceed to the next track. Some of the tracks are closer to each other than others, and which track an electron is on determines how much energy that electron contains. The innermost track requires the least amount of energy, and in every atom the electrons crowd as close to the nucleus as possible. Thus, the innermost track is filled first, and the outermost track is sometimes not filled. If it is not filled, it is possible for an electron from a nearby atom to jump from its track onto the unfilled track of its neighbor. This jumping of electrons creates an electrical current, and atoms with empty spaces in their outermost electron tracks are thus able to be conductors (they are able to conduct electricity).

In order to conduct Medal Day ceremonies properly, The Franklin Institute inquired after the marital status, proper name and title, and university affiliation of its award recipients. In addition, the secretary of the Institute made hotel arrangements for medal winners and invited them to bring guests. You can read the letters regarding Bardeen and Brattain's respective guest lists by clicking on the thumbnails at right.