Some parts at 20 degrees Kelvin and Other at Room Temperature and the Whole Wire still Superconducts

Next Big Future ^ | November 26, 2009 | Brian Wang

[decimon]

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For this to work, the wire's surface must be extremely clean, allowing electrons to move freely and spread along the wire to create a uniform temperature. A material with a critical temperature of -193 °C could superconduct at room temperature, provided some sections were kept to -253 °C, they found. In principle, the colder these refrigeration points are, the fewer you need, Dubi says.

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[Krodg]

huh?

[decimon]

You needn’t supercool the entire wire to achieve superconduction.

[allmost]

They have calculated but has been shown to work?

[omega4179]

is that worth anything without fusion powering it?

[allmost]

The claim is that no disruption of the suppressive effects at low temps occurs when the temp is increased. Considering this is an innate state of the conducting material itself I'm highly skeptical.

[decimon]

They have calculated but has been shown to work?

Not yet tested.

[allmost]

The claim that suppression of the b-field extends beyond the superconductive matter and is somehow ‘projected’ throughout is astounding. The article could be a bit longer. ;)

[DennisR]

The article says:

“According to Yonatan Dubi and Massimiliano Di Ventra of the University of California, San Diego. They have calculated that provided some points along the wire's length stay below the threshold temperature, the material will superconduct.”

It might have something to do with frequency. As you might know, at DC, electricity fills the entire cross-section of the wire. However, as the frequency increases, the electrons move farther away from the center of the wire. It is known as the skin effect and is the result of eddy currents in the wire. Now if the areas where most of the eddy currents are found are kept at a lower temperature, you might be able to achieve superconduction in those areas. Just a guess.

[The Antiyuppie]

This sounds to me like the opposite of “supercooling” - where you can actually have liquid water below 32 degrees F, as long as it’s extremely pure and undisturbed. Dropping a flake of dust or shaking it can cause it to almost instantly freeze. Interesting in a lab, but not very useful.

[allmost]

The temperature difference and hence the superconductivity of the intermittent matter sounds physically impossible. 20 Kelvin adjacent to room temperature? Not with this level of technology.

[allmost]

B-field suppression threshhold is far more extreme than a few degrees at our current level of knowledge. I’d like to read more. Curious now...

[higgmeister]

You needn’t supercool the entire wire to achieve superconduction.

Amazing! If it is corroborated a whole new level of electronics....

[decimon]

The New Scientist article is too short. If you’re really ambitious, there’s a link to the publication with the paper.

[allmost]

At face value, the assertions are revolutionary.

[decimon]

Amazing! If it is corroborated a whole new level of electronics....

I was thinking electronics more than power transmission. If it applies.

[allmost]

Maybe a ping list?

[decimon]

SunkenCiv has been busy discovering his inner Pict.

[allmost]

Sounds painful.

[decimon]

Sounds painful.

You don't feel a thing.

http://www.freerepublic.com/focus/chat/2395530/posts?page=22