What are Cooper pairs

Cooper pairs are pairs of mobile electrons that form at very low temperatures. Each pair consists of two electrons with opposite spin. The electrons share the same wavefunction and are able to pass through the crystal unimpeded. 

Cottrell, 1988, Introduction to the Modem Theory of Metals, Institute of Metals, London. 

The Electronic Stmcture and Chemistry of Solids, Oxford University Press, Oxford. 

Pearson, 1972, The Crystal Chemistry and Physics of Metals and Alloys, Wiley-Interscience, New York, especially Ch. 5. 

Aldissi, 1987, Recent Advances in Inherently Conducting Polymers and Multicomponent Systems , Journal of Materials Education 9 333. 

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