ScienceDaily flooded the place yesterday, to which I'll catch up tonight. We'll start with the "strange metals" and how they conduct electricity. Brown University in the Providence Plantation has the story.
Contrary to headline these are hardly "newly discovered". They're cuprates from around 1992 - so say Brown. Actually a few years before that. We're familiar with them at this blog as the copper-oxides: all that stuff with -co at the end, like bisco and various rebco's. That's right: they're the high-temp superconductors, which we keep running into around here for distributed-power aircraft and for the Ring Of Iron. The article focuses on the yttrium class of rebco, the ybco.
Brown University are, understandably, curious as to how these magic superconductors work. Back in the dark-age of niobium, we had a decent handle on how those worked... at 23 K. The electrons formed "Cooper Pairs" which acted like bosons - like a photon. Sort of like holes in the lattice although those were ionic. Cooper-pair quasibosons are resistant, above superconductive point, linearly with temperature. In normal metals there's some "Fermi liquid" theory that just says, "here's its resistance, for any temperature, until it flat-out melts".
Brown are looking into ybco above the superconducting point, where they're just metals. They say that rebco's are not normal metals; they are "strange". The cooper-pair linear model didn't seem to work. Unless - they say - they open up those holes in the lattice.
Did I understand any of what I just posted? Er... not really. But Brown hope to understand it.
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