(Sorry if I'm using the wrong terms, but I've yet to find any search terms that seem related to what I'm thinking of. If I did know what to search for, I wouldn't be asking this question.)
- Would an accretion disk of plasma around a compact body see enough difference between how the electrons and protons/nuclei orbit to produce a significant net current?
- How much difference in orbits would be needed?
- Is there a name for that (hypothetical) effect?
- Is this a thing anyone has even looked into?
The motivating idea is that if the plasma around a compact body interacted in some way so that the electrons were on average in slightly smaller/faster orbits than the protons (or the other way around) that this would result in a very high effective current around the body (the mobile charge density is way higher than metal and the velocity differences could be a significant fraction of $c$) and should create a powerful magnetic field.
The fact that electrons and protons/nuclei have very large differences in there charge/mass ratio (and several other parameters) suggests that it's not unreasonable expect them to react differently to the environment in an accretion disk.