Question about Superconductivity

[swansont]

How about pathways in processor chips? High-temperature superconducting materials in new CPUs would dramatically increase performance with no heat loss - no heatsink required

 

And spectacular failures when the temperature went above the superconducting threshold...

[swansont]

How "small" has a superconductor been made in a lab? What is the current record for the "smallest superconductor" and the "smallest magnet"?

 

I don't know what the record is, but superconductors have been made smaller than 1 micron on a side for superconducting quantum interference devices (SQUIDS). This abstract mentions one that is 200 nm on a side.

[labview1958]

Thanks SWANSON,

 

Actually I am looking for superconducting samples the size of 1 mm. to do some testing. Right now I have some superconducting discs with a diameter of 20 mm. I was wondering whether if I break up my discs into particles of 1mm, will they still be superconducting? Or would they lose their superconducting property? Is the size relevant for a material to superconduct?

[5614]

Size is relevant, however not in the way that you mean.

 

If you break up your superconducting chip it should still work at 1mm.... however remember that less current will be able to flow (as there are less electrons in the vastly smaller area), which will result in a smaller magnetic field and smaller current... although this is possibly what you want?

[labview1958]

If I break a superconducting chip into 100 pieces. Would the total superconducting strength be equal to the uncut chip in terms of the meissner effect?

[5614]

What do you mean by superconducting strength?

 

You say in terms of the meissner effect, so do you mean in terms of how strong the magnetic field is?

 

If so then surely a smaller superconducting chip, with its smaller volume and consequent smaller number of electrons will produce a smaller magnetic field.

[labview1958]

I agree each small chip will produce a corresponding smaller magnetic field. However does 100 small chips produce the same amount of magnetic field as one big chip? Let's say a 100 gram magnet is lifted 10 cm by the big chip, would 100 broken pieces of this big chip lift the 100 gram magnet by 10 cm?

[5614]

That's a difficult question to answer, not knowing the answer here's what I'd guess:

 

It's got nothing to do with surface area, but because the chips would be more spread out the magnetic field is not going to be as intense in each area, it'd be weaker, but would cover a slightly larger area... because once you cut up the superconductor it will not be as compact.

 

I'd say it'd be quite close to lifting 100g, only through experiment could you work out the possibly tiny change.