I have been wondering whether or not applying a magnetic field to a material containing magnetic spins could produce an electrostatic-like field as a result of a Larmor precession of the embedded magnetic spins. I have found an article which claims that this happens:


Current electric quadrupole moments of atoms and nuclei


It is shown that current electric multipoles exist. Their field is electrostatic and it is unrelated to the existence of a net electric charge. At long range, it is the same as the field of the corresponding charge electric multipoles. Current electric multipoles arise during the motion of magnetic multipoles. An orbital motion of magnetic dipoles, a precession of a current-carrying loop, and the motion of magnetic quadrupoles all lead to current electric quadrupole moments. Expressions for the current electric quadrupole moments of atoms and nuclei are derived.

Thus, it seems to me that the amount of "electrostatic" work that could be done by the resultant electric quadrupoles is only limited by the magnitude of electric charges in proximity to the precessing magnetic spins and the distance that they are able to move as a result. Yet the presence of such charges, if I understand correctly, should have no effect on the Larmor frequency that results from the magnetic field which we apply. Thus, the amount of work done by the generated electric field appears to have some degree of independence relative to the amount of work required to set up the Larmor precession of the magnetic spins. It is unclear to me how, or even if, the latter is the upper limit of the former.

So is it really true that magnetic spins undergoing Larmor precession will generate such electrostatic-like fields capable of doing work on neighboring electrical charges in a sort of capacitive-coupling interaction? And if so, how could the work done on such charges by this electric field be limited relative to the amount of work required to set up the Larmor precession of the magnetic spins?


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