The first thing you learn in electrical engineering is Ohm’s Law, which basically says that toaster and hair dryer wires get hot. To use the first-grade science analogy, just like sticks get hot when you rub them, wires get hot when the moving electrons that make up electricity rub against the metal atoms in the wire. Then in 1911 a Dutch physicist named Heike Onnes discovered superconductivity – get a wire cold enough, the atomic crystaline structure in a wire “smooths out” so the rush of electrons produces no “friction” or waste heat at all. (Hey, you’re ready for physics PhD prelim exams with an explanation like that!) Problem is, Dr. Onnes and those who came after him could only get it to work if super-cold (and expensive) liquid helium was used as the coolant. In 1986, a new category of so-called “high-temperature” superconductors were discovered, but the term was relative – you still needed super-cold (but fairly common and not so expensive) liquid nitrogen to get this type of superconductor to work. Plus, these were ceramics, not metals, so making wire was an exercise in frustration that has hampered technological utilization. Worth a Nobel Prize, though, and made a few scientific careers…
Since then the goal has been to create some kind of superconducting material that needed no coolant at all to work – so called “room temperature” superconductors. The things you could do with such a material boggles the imagination – it would almost be as good as going from the Stone Age to the Metal Age. Now a scientist in South Africa says he’s found such a material – not a metal, not a ceramic, but diamond that’s been treated with oxygen. Results from his experiments have been published in a special issue of Semiconductor Science and Technology (18 S131). “If it is not superconductivity then it must be violating the second law of thermodynamics,” says Johan Prins of the University of Pretoria. However, the rest of the diamond community remains to be convinced. Richard Jackman of University College London, who edited the special issue of the journal in which Prins’ papers appear, describes them as “largely theoretical papers, thought provoking and very controversial – the end conclusions remain open to debate”. Prins is half-way through writing six theoretical papers that will, he claims, fully explain the results and shed new light on the mechanisms underlying high-temperature superconductivity. He has offered to fly his samples to another lab for independent verification but has not yet found any volunteers. Don’t worry, he will – his claim is the stuff of which dreams are made.
Rather unfortunate that (assuming the story is true), room temperature superconductivity requires one the most expensive materials on earth.
If diamond can be made to superconduct in very small quantities – in integrated circuits, for example – the applications are limitless.
But on larger scales, I wonder what would be cheaper, a diamond superconducting wire, or a ceramic superconductor with a cooling system?
Anyway, whether it’s practical or not, I’m sure it’s an important breakthrough – and will lead to a better understanding of usable superconducting materials, at least.
Could this mean the demand for, (and therefore price of) diamonds will go up? I assume this method would use artificial diamonds, so maybe not.
The Russians are making very good synthetic diamonds.
Synthetic diamonds are actually more perfect than the natural ones, and way cheaper, so they would likely be a better choice for superconductors anyway.
Regardless, diamonds are a big scam. Their high price is an entirely artificial construct. There’s an excellent article from Atlantic Monthly about how the North American market was duped. To quote one paragraph:
Quoting from the paper:
So it’s not just limited to ‘room temperature’, which is important, because you wouldn’t want your superconducting device to stop working just because the sun shone on it for a while.
Wonder how long it’ll take to find out if this is for real or not?
read it and weep. :(
Didn’t realize ’til now that I hadn’t included the actual link. Thanks!
If this is really purely theoretical I wouldn’t trust it too far (I worked with somebody for a while who claimed metallic hydrogen would be superconducting at room temperature – based on theoretical considerations, and if you could ever get some room-temperature metallic hydrogen…)
But carbon is already heavily involved in an intriguing number of different superconducting compounds – including things I worked on myself for a while. Planar graphite intercalated (layered) with alkali metals forms low-temperature superconducting compounds, and compounds of alkalis and buckyballs (C-60) make some reasonably high-temperature superconductors (30 K or so). There are also some organic chemicals with crystalline forms that superconduct at low temperatures.
Diamond’s structure is of course quite different from graphite or C-60; in fact the carbon atoms in diamond are a little further apart than those in the graphite layers (single vs. half-single/half-double bonds). But the binding is very strong, and that’s one factor that can conceivably lead to high-temperature superconductivity. You never know with this stuff until several researchers have been able to test it – interesting idea anyway.
That’s celsius. 80 C is a lot hotter than you’d be comfortable touching. Remember, 100 C is the boiling point of water (at 1 atmosphere).
I’d be pretty happy with a superconductor that worked IN THE SHADE, much less one that could make your skin sizzle.