The Field Induced in a Conducting Sphere Placed in a Steady Magnetic Field and a Perpendicular Oscillatory Magnetic Field

摘要

The fields induced in a conducting sphere of conductivity eta, placed in a strong steady magnetic field B sub (a) z, and a small oscillatory magnetic field (in the XY plane) of magnitude B sub omega were calculated approximately for: B sub omega/B sub (a) 1 and B sub (a)/ne(eta) 1, where n is the number density. The conducting sphere is assumed to have a uniform resistivity and number density and the ions are assumed immobile. It was shown that: (1) if the applied oscillatory field is linearly polarized, the magnetic field induced in the conducting sphere has a rotating component for which omega (vector) is parallel to B sub (a) z; (2) if the applied oscillatory field is rotating (circularly polarized), its penetration in the conducting sphere is enhanced or impeded with respect to the classical skin effect depending on whether the sense of rotation is parallel or antiparallel to B sub (a) z. These results are consistent with the experimental observation in the rotating field plasma experiments.