I Is there such a thing as an active diamagnet?

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Active diamagnets, which would require a power source to block external magnetic fields, are not commonly recognized in scientific literature. The discussion highlights that traditional methods for magnetic shielding typically utilize materials like mu-metal, which do not require an active power source. The concept of an active diamagnet remains largely theoretical, as no practical examples have been identified. The need for such a device arises in situations where superconductors are impractical. Overall, the feasibility of active diamagnets is still uncertain within current technology.
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Does something like an active diamagnet exist for when you need to block external magnetic fields, but a superconductor wouldn't be practical?
 
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What do you mean by "active" diamagnet?
 
cuallito said:
Does something like an active diamagnet exist for when you need to block external magnetic fields, but a superconductor wouldn't be practical?
If by ‘active’ you mean something that requires a power source (e.g. requires a current), then I’’ve never heard of one. For simple magnetic shielding, an alloy called ‘mu-metal’ is often used. E.g. see https://en.wikipedia.org/wiki/Mu-metal.
 
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