Electrostatic potential and magnetic moment of radially insulating Corbino disk

Abstract

We solve analytically a three-dimensional Poisson equation for the potential produced by two coaxial metallic contacts at the edges of the Corbino disk. It is assumed that there is a finite tangential current, while the radial current is absent. This solution is compared with a solution of the two-dimensional problem for conducting Corbino disk. We calculate the magnetic dipole moment of Corbino disk and compare our results with the case of two-dimensional Coulomb distribution of the potential which is realized in Corbino disk in the presence of the radial current. We also discuss the application of torque magnetometry to study metal–insulator transition, in particular, in the quantum Hall regime. • Radially insulating Corbino disk. • Two-dimensional vs three-dimensional Coulomb potential. • Magnetic moment.