I am a fan and I often read your answers. Your recent reply on eddy currents is of particular interest to me. The topic is eddy currents..and I quote ...
"Eddy currents are dictated by local atomic and molecular states and are the direct result of quantum mechanical rules regarding electronic states near nuclei." I googled eddy currents and all the articles only state the macro properties. I am interested in the quantum properties as stated in your reply. Can you elaborate a bit more or point me to some reference or books? Thanks
Hi Ayee... Sorry for the delay:
The bulk properties that are usually discussed are merely the ensemble of all of the many nano and micro eddy currents in a material at a given time. In order to experimentally observe and measure the nanoscale eddy currents that give rise to bulk effects, you effectively have to look at EM field effects on nanomaterials. That is to say, in a large system, a nano/quantum level eddy is non-observable. I'll give a couple ideas for where to look below
The majority of research in the field has been focused on two applications: Superconduction and heat therapies for medical applications.
Where to look will all depend on how much access you have to articles. Here is a free one on-line describing how the use of eddy currents in a nanoparticle can be used for to generate localized heat.
If you search for eddy current + nanoparticle, you will find quite a few articles and web pages.
For superconductors, the interest is in being able to see the special change in state that occurs as temperature drops to a point where a material becomes free of eddy currents that hinder charge transport and electrons become free to flow virtually unhindered.
In a general sense, any book on solid state physics should be able to get you going in the right direction. Depending on how strong your math is, these class notes from Steve Errede, a professor at the University of Illinois Urbana-Champagne, may be helpful.
Even if your math skills are nowhere near the level discussed, his sketches are very good - specifically the one where he places many small circular currents inside a larger conductive object.
As a final note: If you do find an introduction to solid state physics book, I just wanted to give you a pointer on two terms to look for.
The first is phonon - this is a packet of energy in a solid material associated with heat and atomic vibrations and which acts very much like a wave.
The second is plasmon - which is a localized oscillation of the electronic cloud (plasma) in a material that can move (sometimes) and decays very rapidly.
Both are important to understanding eddy currents, so I just wanted to let you know to look for when they come up.
Best of luck!