Posted on 03/25/2011 3:27:53 PM PDT by decimon
Kinetic on pseudogap ping.
My labradoodle eats pseudogaps.
When did lead bismuth strontium lanthanum copper-oxide become a single material?
When the dish ran away with the spoon? Beats me.
Just another alloy, with interesting electrical properties.
Right after the divorce
hehe he heh.. heh.. He said ‘kinetic’ heh.. heh.. he hehe.
Makes sense it would be, I think.
How could it superconduct unless it had all it’s ducks in a row?
“When did lead bismuth strontium lanthanum copper-oxide become a single material? “
Like yttrium barium copper oxide, (YBa2Cu3O7-x), it is an oxide containing several metal ions. Each one must be given in the name.
I should have added, yttrium barium copper oxide was the first high temperature superconductor to exhibit superconductivity above the boiling point of liquid nitrogen (T=77K, -196C). It goes superconducting at 93K (-180C).
Physics Ping!!
The key ingredient in the High Tc materials are naturally-ocurring 2-dimensional substrates of CO2.
The High Tc materials are “Jahn-Teller distort materials” - which simply mean that they contain these stable sheets of CO2. Playing around with the other materials changes the hole-doping of the CO2.
Antiferromagnetic exchange between hole-pairs acts as an attractive force between hole pairs on this sort of lattice, but it doesn’t by itself beat charge repulsion.
I left the field before the correct pairing mechanism was identified - if it has indeed yet been identified. The leading theory (IIRC) of the hole-pairing involved not pairing, but collective behaviour due to the fractional quantum Hall effect which can only occur on 2-and-a-bit-dimensional lattices such as these JT-distort lattices.
Do you happen to know what the critical magnetic field is on the YBa2Cu3O7-x family?
What I really want to know is the supportable current density. Does a temp lower than 77K help in this regard?
IIRC about 100 T. The critical current depends on direction relative to the CUO2 plane.
Ouch, after midnight. Goodnight all.
three complementary experimental approaches to investigate a single material, the high-temperature superconductor Pb-Bi2201 (lead bismuth strontium lanthanum copper-oxide)... are the strongest evidence yet that the pseudogap phase, a mysterious electronic state peculiar to high-temperature superconductors, is not a gradual transition to superconductivity in these materials, as many have long believed. It is in fact a distinct phase of matter.Pb stands for Pepto-Bismol, and this research isn't done with its investigation of antacids.
Solid, Liquid, Gas, Plasma, and Superconductivity?
That sounds like a whole lotta current density.
But then again, I haven’t had to do that calculation since MetEng 221 (or was it Phys 363?) in 1968.
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