What is Cooper pair?

Answer 1

A Cooper pair is a fundamental concept in superconductivity, referring to a pair of electrons that are bound together at low temperatures through attractive interactions mediated by lattice vibrations (phonons). These pairs exhibit a collective behavior that allows them to move through a superconducting material without resistance. The formation of Cooper pairs is essential for the onset of superconductivity, as it leads to a macroscopic quantum state that can carry electrical current without energy loss.