A Superconductor ring: shielding currents in different directions

annaphys
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In this photo you see on the right-hand side that the outer wall current is negative and the inner wall current is positive. That is, they are directed in different directions. But if the applied magnetic field is in the z direction as shown, then shouldn't they both be in the same direction do to the fact that j_s = -j = rotB? That is the shielding current goes in the opposite direction of the current caused by the magnetic field. Why is it so that the currents are in different directions?
Yi8cR.png
 
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Another question, why is rotB=mu*j_s? Shouldn't j_s would against the magnetic field so it should that rotB= mu*j where j = -j_s?
 
Nevermind I understand it. My assumption from the beginning was wrong. There isn't a continuous homogeneous mag field in the photo just the trapped field.
 
From the BCS theory of superconductivity is well known that the superfluid density smoothly decreases with increasing temperature. Annihilated superfluid carriers become normal and lose their momenta on lattice atoms. So if we induce a persistent supercurrent in a ring below Tc and after that slowly increase the temperature, we must observe a decrease in the actual supercurrent, because the density of electron pairs and total supercurrent momentum decrease. However, this supercurrent...
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