I Superconductors and moving/accelerating charges

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Electrons in superconductors move as Cooper pairs, which are quantum mechanical entities rather than classical charges. The Meissner effect occurs when these pairs are already in motion, indicating that the superconducting state is maintained without classical trajectories. Accelerating Cooper pairs can theoretically happen, but applying external forces risks disrupting the superconducting state. Unlike classical charges, Cooper pairs do not emit photons when accelerated, as their behavior is governed by quantum mechanics. Understanding superconductors requires a shift from classical concepts to a focus on the unique properties of Cooper pairs.
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I have some questions about the charges within the superconductor and how they is set in motion and whether or not the charges within a superconductor can accelerate, and if not why not? Because I suppose that would mean applied force and destruction of the superconducting state. But if yes why? And does that acceleration emit photons? I assume no because the superconductor is a condensate(collective ground state, and the ground state can't emit photons).
How do one get the electrons to move inside a superconductor? Since I have understood superconductors repel magnetic fields due to the Meissner effect, or is that when the charges already are moving within the superconductor? If so how did we get them o move from the beginning?

Can you make charges accelerate within a superconductor? If yes how? Or will the applied force to make the charges accelerate destroy the superconducting state of the system? And if they can accelerate will they then emit photons, as normal accelerating charges?

If you know some good literature for these topics, please attach it, I would appreciate it!
 
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Classical "charges" is the wrong way to thinking about it, The charge carriers are Cooper pairs, which are fundamentally non-classical objects. Discussing classical trajectories will hinder rather than help understanding.
 
Vanadium 50 said:
Classical "charges" is the wrong way to thinking about it, The charge carriers are Cooper pairs, which are fundamentally non-classical objects. Discussing classical trajectories will hinder rather than help understanding.
Thanks for clarifying! From a perspective of Cooper pairs how would you answer my questions?
 
The same way - they don't have classical trajectories either. (And you can't easily say "that electron over there makes a Cooper pair with this electron right here". QM isn't like that)
 
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...