Anomalous electron trapping by magnetic flux tubes and electric current vortices

Abstract

We consider an electron with an anomalous magnetic moment, g>2, confined to a plane and interacting with a nonhomogeneous magnetic field B, and investigate the corresponding Pauli Hamiltonian. We prove a lower bound on the number of bound states for the case when B is of a compact support and the related flux is $N+\epsilon ,\epsilon \in (0,1]$. In particular, there are at least N+1 bound states if B does not change sign. We also consider the situation where the magnetic field is due to a localized rotationally symmetric electric current vortex in the plane. In this case the flux is zero; there is a pair of bound states for a weak coupling, and higher orbital-momentum "spin-down" states appearing as the current strength increases.

6 pages, LaTeX, to appear in Proceedings of QMath7, Prague 1997, published in the Birkhauser series "Operator Theory: Advances and Applications; the final version with a correction in Thm 2