And as of 2015, we have achieved superconductivity above 200 K! (Albeit at super extreme pressures.) As usual, the discovery has no immediate commercial application, but it is noteworthy nonetheless for a few reasons. First, it’s notable for being a conventional superconductor rather than an unconventional superconductor (it’s the unconventional ones that have been breaking the records prior). Second, and semi-related to the first, it is one of the few examples of a superconductor being predicted before it was measured. And now that I think about it, there is no third notable aspect. But I guess breaking a world record is notable!
One mistake that people make too often is thinking that a room temperature superconductor would be world-changing. Even if we synthesized such a substance, there’d be many other materials-related hurdles to jump before we could start replacing power lines with superconductors. Hurdles like cost (“I’m not buying a $100 cable to save $1 on electricity”), thermal stability (“It melted after one week!”), critical field (“It carries electricity for free, but only 1 milliamp?”), tensile strength (“Oops, I guess we can’t hang them from poles”), brittleness (“Wait, I paid for a cable that cannot bend?”), sensitivity to heat (“Well, it was superconducting before the summer heat wave”), critical field again (“Wait, so I never need to charge my electromagnet anymore but now it’s weaker than a permanent magnet?”), and so forth. I apologize for being such a pessimist. But the fact is that we already have stuff that superconducts at liquid nitrogen temperatures (which is super cheap compared to helium), and yet commercial applications remain rare.
More analysis coming soon.