Wednesday, June 30, 2010

Superconductors everywhere

kw: observations, physics

I read in an article an analogy to explain the orbital restrictions of electrons in atoms. The electron's "orbit" was compared to an organ pipe, which makes a particular tone because of a standing wave within it. Just as a standing wave doesn't "go anywhere", the electron forms a standing wave and doesn't go anywhere. Thus, it does not experience acceleration. This is important because a charged particle that experiences acceleration must emit radiation. Our entire electrical economy is built on this principle!

The electron, then, does not orbit the nucleus, strictly speaking, but forms a standing wave and remains stable. However, the source of the analogy, the organ pipe, is not stable. One must supply energy because the tone it emits removes energy from the system. There is, however, a standing wave system, which can be the size of an organ pipe, that does not emit any energy and is stable. That is a superconducting magnet. One uses conventional leads to feed current into a superconducting magnet to build up its magnetic field, then adds a superconducting link to short across the leads' terminals and switches out the leads. This system is stable, emits no radiation, and maintains the magnetic field until a resisting link is introduced to absorb the energy. Both charging and discharging a superconducting magnet must be done carefully, because some of them store the energy of a few sticks of dynamite.

Compare with a hydrogen atom. Its single electron is a stable standing wave that emits no radiation and maintains a magnetic field. A lone atom of hydrogen is a tiny magnet (but hydrogen normally exists in H2 molecules that pair up like two magnets stuck together, leaving no residual field). In this atomic magnet, the electron is effectively a superconductor! Superconductivity is a quantum property of electrons in their stable orbitals. It is fundamentally different from Cooper pair-induced superconductivity.

If this kind of quantum superconductivity could be expanded to large scales, room-temperature (and above) superconducting devices could become a reality. Ferromagnetism is one expression of intrinsic electron magnetic orientation, but is inefficient, because the electron that produces the magnetic field needs at least 25 "friends" to support the magnetic asymmetry required.

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