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Why superconductivity?
Superconductivity—the conduction of electrons through materials
with zero resistance—is an impressive example of emergent behavior
at the quantum scale: unexpected order, collective behavior, and entirely
new states brought about by complex interactions between simple components.
In addition, it’s one of the few opportunities for us to see quantum
properties on a macroscale.
For 50 years after it was discovered, even the greatest scientists such as Richard Feynman were stumped as to how it worked. In 1957, three scientists (Bardeen, Cooper, and Schrieffer; BCS) showed how superconductivity was created by a hidden electronic order. Their explanation was based on a new concept: at extremely low temperatures it is “quiet” enough that electrons can feel the motions of their neighbors, and thus are swept along in their wake, forming "Cooper pairs" which enter a coherent dance that allows them to flow without bumping into each other or the atoms in the metal.
ICAM is especially well positioned to educate the public on the topic of superconductivity. ICAM’s member universities and national labs house top superconductivity researchers who are eager to explain their work to the public. The EUP seeks to develop outreach projects on superconductivity in time to celebrate the upcoming fiftieth anniversary, in 2007, of the seminal Bardeen-Cooper-Schrieffer paper on superconductivity.
Many of the concepts in superconductivity may be easily introduced using
magnetism, an emergent phenomenon that is more familiar. Even young children
know about the odd behaviors of magnets—how nonmagnetic metals are
attracted to magnets and become magnetized themselves; how the opposite
poles of magnets repel each other; and the ability of magnets to maintain
their attractive power through nonmetallic substances. Magnetism is a
familiar example of quantum emergence —the electron spins (define)
align within the metal. Concepts related to the quantum world, such as
electron charge and spin, can be introduced using magnetism.
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