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A comment on LK99: Team of Southeast University observed zero resistance below 110 K. Parent comment

Re:LK99: Team of Southeast University observed zero resistan... by Laforet on Wednesday August 02, 2023 @04:47PM (#36977168)
Flux pinning of a superconductor should be able to hold it steady below a magnet, and the magnet should be able to drag the superconductor with it when moving (within reasonable weight limits of course). These will demonstrate for sure that levitation is not simply a force equilibrium between gravity, magnetic repulsion and one corner of the material resting on the surface.

There is a video from the Korean team showing LK99 moving when both poles of a large magnet is swung nearby, however the effect was a bit weak to conclusive.

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Re:LK99: Team of Southeast University observed zero resistan... by uyhgr on Wednesday August 02, 2023 @05:24PM (#36977738)
Correct, the imperfections of the crystal allowing the flux pinning permits even a “hanging levitation”. Here is a timestamped video showing that:

https://m.youtube.com/watch?v=Ws6AAhTw7RA&t=90

If we develop methods of creating these superconductors with perfect crystal composition then there will only be the repulsion, allowing for levitation in a bowl shaped superconductor, but this “hanging levitation” would be impossible.

Perhaps we will develop manufacturing techniques to induce specific imperfections into the material to ensure predictable flux pinning.

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