John Bardeen
Electrical Engineer
John Bardeen was the first physicist to receive two Nobel prizes in the same field. Bardeen got his first Nobel prize in 1956 for his collaboration on the research over semiconductors and the discovery of the transistor effect.
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He later was recognized in that same field for his joint development of the Superconductivity also known as the BCS Theory with Cooper and Schrieffer winning them a Nobel prize in 1972.
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The transistor is one of the most influential inventions in the twentieth century. The BCS theory became known once John argued that the "Theory of the Meissner effect in superconductors" He believe that "such a modification naturally occurs in a theory with an energy gap. The key ingredient was Leon Neil Coopers calculation of the bound states of elections subject to an attractive force. "Bound Election pairs in a Degenerate Fermigas." John then gathered all ingredients and constructed his theory with cooper Schrieffer.