Talk:BCS theory

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This article may be too technical for a general audience. Please help improve this article by providing more context and better explanations of technical details to make it more accessible, without removing technical details.

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Some diagrams or pictures might help this article

[edit] Intuitive picture is wrong (?)

The BCS theory page has an intuitive explanation of how Cooper pairs are formed (see below). I think this picture is not suitable, as it is wrong.

Cooper pairs are formed between electrons with opposite spin, and opposite k-vector. This means they have to be travelling in opposite directions! The energy of such a system is lowered compared to the two separate systems, because the center of mass is at rest.

[edit] Text from article

Roughly speaking the picture is the following:

An electron moving through a conductor will attract nearby positive charges in the lattice. This deformation of the lattice causes another electron, with opposite "spin", to move into the region of higher positive charge density. The two electrons are then held together with a certain binding energy. If this binding energy is higher than the energy provided by kicks from oscillating atoms in the conductor (which is true at low temperatures), then the electron pair will stick together and resist all kicks, thus not experiencing resistance.

[edit] Cleanup tag

I notice the cleanup tag on the article since July 2007. I agree that the article needs improving; however, tags should not just be added with no explanation on the talk page, so I'll remove the tag for now. What are some specific suggestions for improving this article?--Gloriamarie 17:12, 11 September 2007 (UTC)

I feel its a bit too wordy. And even so, the explanations given are too short for anyone to clearly understand.

Eg: The ratio between the value of the energy gap at zero temperature and the value of the superconducting transition temperature (expressed in energy units) takes the universal value of 3.5, independent of material.

I'm pretty sure the first qns asked of that line would be: what is that 3.5 of what universal value of what zero temperature gap?

Put simply, there are many descriptions about the bcs theory in the article, but its jus not organized into a simple understandable way.

I support the cleanup tag reinstated--Venny85 17:13, 29 March 2008 (UTC)