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Electrons vs Cooper Pairs
Quantum Statistics:
Occupying Energy Levels
Quantum particles fill energy levels differently depending upon a property they possess known as spin. If they possess half-integer spin they will obey Fermi-Dirac statistics. If the particles have integer spin, they obey Bose-Einstein statistics.
n = 1 n = 2 n = 3 n = 4 Energy
Half-integer particles Spin e.g. electrons
Integer particles Spin e.g. Cooper pairs
 
Applying an Electric Field:
Metals vs Superconductors
When an electric field is applied to materials, the electrons within it will aquire momentum. However, free electrons and Cooper pairs do this in a different way.
− +
Metals: e.g. electrons
Superconductors e.g. Cooper pairs
 
Superconductors:
Origin of the energy gap
One of the defining characteristics of superconductors is the fact that they have a gap between the filled and unfilled states in their band structure.
 
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binding energy band formation Energy Occupied Empty
Binding energy
Effect on band structure